37 Dplyr Training Exercise.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Dplyr Exercises\n",
    "\n",
    "Perform the following operations using only the __dplyr__ library. We will be reviewing the following operations\n",
    "\n",
    "- __filter()__\n",
    "- __slice()__\n",
    "- __arrange()__\n",
    "- __select()__\n",
    "- __rename()__\n",
    "- __distinct()__\n",
    "- __mutate()__\n",
    "- __transmute()__\n",
    "- __summarise()__\n",
    "- __sample_n()__\n",
    "- __sample_fract()__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [],
   "source": [
    "library(dplyr)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We will use the mtcars dataframe for these exercise!"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "df <- head(mtcars,12)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 1) Return the rows of cars that have an mpg value greater than 20 and have 6 cyilnders "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 3 × 11</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>mpg</th><th scope=col>cyl</th><th scope=col>disp</th><th scope=col>hp</th><th scope=col>drat</th><th scope=col>wt</th><th scope=col>qsec</th><th scope=col>vs</th><th scope=col>am</th><th scope=col>gear</th><th scope=col>carb</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160</td><td>110</td><td>3.90</td><td>2.620</td><td>16.46</td><td>0</td><td>1</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160</td><td>110</td><td>3.90</td><td>2.875</td><td>17.02</td><td>0</td><td>1</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>21.4</td><td>6</td><td>258</td><td>110</td><td>3.08</td><td>3.215</td><td>19.44</td><td>1</td><td>0</td><td>3</td><td>1</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 3 × 11\n",
       "\\begin{tabular}{lllllllllll}\n",
       " mpg & cyl & disp & hp & drat & wt & qsec & vs & am & gear & carb\\\\\n",
       " <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl>\\\\\n",
       "\\hline\n",
       "\t 21.0 & 6 & 160 & 110 & 3.90 & 2.620 & 16.46 & 0 & 1 & 4 & 4\\\\\n",
       "\t 21.0 & 6 & 160 & 110 & 3.90 & 2.875 & 17.02 & 0 & 1 & 4 & 4\\\\\n",
       "\t 21.4 & 6 & 258 & 110 & 3.08 & 3.215 & 19.44 & 1 & 0 & 3 & 1\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 3 × 11\n",
       "\n",
       "| mpg &lt;dbl&gt; | cyl &lt;dbl&gt; | disp &lt;dbl&gt; | hp &lt;dbl&gt; | drat &lt;dbl&gt; | wt &lt;dbl&gt; | qsec &lt;dbl&gt; | vs &lt;dbl&gt; | am &lt;dbl&gt; | gear &lt;dbl&gt; | carb &lt;dbl&gt; |\n",
       "|---|---|---|---|---|---|---|---|---|---|---|\n",
       "| 21.0 | 6 | 160 | 110 | 3.90 | 2.620 | 16.46 | 0 | 1 | 4 | 4 |\n",
       "| 21.0 | 6 | 160 | 110 | 3.90 | 2.875 | 17.02 | 0 | 1 | 4 | 4 |\n",
       "| 21.4 | 6 | 258 | 110 | 3.08 | 3.215 | 19.44 | 1 | 0 | 3 | 1 |\n",
       "\n"
      ],
      "text/plain": [
       "  mpg  cyl disp hp  drat wt    qsec  vs am gear carb\n",
       "1 21.0 6   160  110 3.90 2.620 16.46 0  1  4    4   \n",
       "2 21.0 6   160  110 3.90 2.875 17.02 0  1  4    4   \n",
       "3 21.4 6   258  110 3.08 3.215 19.44 1  0  3    1   "
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 2) Reorder the data frame by cyl first, then by descending wt"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 12 × 11</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>mpg</th><th scope=col>cyl</th><th scope=col>disp</th><th scope=col>hp</th><th scope=col>drat</th><th scope=col>wt</th><th scope=col>qsec</th><th scope=col>vs</th><th scope=col>am</th><th scope=col>gear</th><th scope=col>carb</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>24.4</td><td>4</td><td>146.7</td><td> 62</td><td>3.69</td><td>3.190</td><td>20.00</td><td>1</td><td>0</td><td>4</td><td>2</td></tr>\n",
       "\t<tr><td>22.8</td><td>4</td><td>140.8</td><td> 95</td><td>3.92</td><td>3.150</td><td>22.90</td><td>1</td><td>0</td><td>4</td><td>2</td></tr>\n",
       "\t<tr><td>22.8</td><td>4</td><td>108.0</td><td> 93</td><td>3.85</td><td>2.320</td><td>18.61</td><td>1</td><td>1</td><td>4</td><td>1</td></tr>\n",
       "\t<tr><td>18.1</td><td>6</td><td>225.0</td><td>105</td><td>2.76</td><td>3.460</td><td>20.22</td><td>1</td><td>0</td><td>3</td><td>1</td></tr>\n",
       "\t<tr><td>19.2</td><td>6</td><td>167.6</td><td>123</td><td>3.92</td><td>3.440</td><td>18.30</td><td>1</td><td>0</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>17.8</td><td>6</td><td>167.6</td><td>123</td><td>3.92</td><td>3.440</td><td>18.90</td><td>1</td><td>0</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>21.4</td><td>6</td><td>258.0</td><td>110</td><td>3.08</td><td>3.215</td><td>19.44</td><td>1</td><td>0</td><td>3</td><td>1</td></tr>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160.0</td><td>110</td><td>3.90</td><td>2.875</td><td>17.02</td><td>0</td><td>1</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160.0</td><td>110</td><td>3.90</td><td>2.620</td><td>16.46</td><td>0</td><td>1</td><td>4</td><td>4</td></tr>\n",
       "\t<tr><td>16.4</td><td>8</td><td>275.8</td><td>180</td><td>3.07</td><td>4.070</td><td>17.40</td><td>0</td><td>0</td><td>3</td><td>3</td></tr>\n",
       "\t<tr><td>14.3</td><td>8</td><td>360.0</td><td>245</td><td>3.21</td><td>3.570</td><td>15.84</td><td>0</td><td>0</td><td>3</td><td>4</td></tr>\n",
       "\t<tr><td>18.7</td><td>8</td><td>360.0</td><td>175</td><td>3.15</td><td>3.440</td><td>17.02</td><td>0</td><td>0</td><td>3</td><td>2</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 12 × 11\n",
       "\\begin{tabular}{lllllllllll}\n",
       " mpg & cyl & disp & hp & drat & wt & qsec & vs & am & gear & carb\\\\\n",
       " <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl>\\\\\n",
       "\\hline\n",
       "\t 24.4 & 4 & 146.7 &  62 & 3.69 & 3.190 & 20.00 & 1 & 0 & 4 & 2\\\\\n",
       "\t 22.8 & 4 & 140.8 &  95 & 3.92 & 3.150 & 22.90 & 1 & 0 & 4 & 2\\\\\n",
       "\t 22.8 & 4 & 108.0 &  93 & 3.85 & 2.320 & 18.61 & 1 & 1 & 4 & 1\\\\\n",
       "\t 18.1 & 6 & 225.0 & 105 & 2.76 & 3.460 & 20.22 & 1 & 0 & 3 & 1\\\\\n",
       "\t 19.2 & 6 & 167.6 & 123 & 3.92 & 3.440 & 18.30 & 1 & 0 & 4 & 4\\\\\n",
       "\t 17.8 & 6 & 167.6 & 123 & 3.92 & 3.440 & 18.90 & 1 & 0 & 4 & 4\\\\\n",
       "\t 21.4 & 6 & 258.0 & 110 & 3.08 & 3.215 & 19.44 & 1 & 0 & 3 & 1\\\\\n",
       "\t 21.0 & 6 & 160.0 & 110 & 3.90 & 2.875 & 17.02 & 0 & 1 & 4 & 4\\\\\n",
       "\t 21.0 & 6 & 160.0 & 110 & 3.90 & 2.620 & 16.46 & 0 & 1 & 4 & 4\\\\\n",
       "\t 16.4 & 8 & 275.8 & 180 & 3.07 & 4.070 & 17.40 & 0 & 0 & 3 & 3\\\\\n",
       "\t 14.3 & 8 & 360.0 & 245 & 3.21 & 3.570 & 15.84 & 0 & 0 & 3 & 4\\\\\n",
       "\t 18.7 & 8 & 360.0 & 175 & 3.15 & 3.440 & 17.02 & 0 & 0 & 3 & 2\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 12 × 11\n",
       "\n",
       "| mpg &lt;dbl&gt; | cyl &lt;dbl&gt; | disp &lt;dbl&gt; | hp &lt;dbl&gt; | drat &lt;dbl&gt; | wt &lt;dbl&gt; | qsec &lt;dbl&gt; | vs &lt;dbl&gt; | am &lt;dbl&gt; | gear &lt;dbl&gt; | carb &lt;dbl&gt; |\n",
       "|---|---|---|---|---|---|---|---|---|---|---|\n",
       "| 24.4 | 4 | 146.7 |  62 | 3.69 | 3.190 | 20.00 | 1 | 0 | 4 | 2 |\n",
       "| 22.8 | 4 | 140.8 |  95 | 3.92 | 3.150 | 22.90 | 1 | 0 | 4 | 2 |\n",
       "| 22.8 | 4 | 108.0 |  93 | 3.85 | 2.320 | 18.61 | 1 | 1 | 4 | 1 |\n",
       "| 18.1 | 6 | 225.0 | 105 | 2.76 | 3.460 | 20.22 | 1 | 0 | 3 | 1 |\n",
       "| 19.2 | 6 | 167.6 | 123 | 3.92 | 3.440 | 18.30 | 1 | 0 | 4 | 4 |\n",
       "| 17.8 | 6 | 167.6 | 123 | 3.92 | 3.440 | 18.90 | 1 | 0 | 4 | 4 |\n",
       "| 21.4 | 6 | 258.0 | 110 | 3.08 | 3.215 | 19.44 | 1 | 0 | 3 | 1 |\n",
       "| 21.0 | 6 | 160.0 | 110 | 3.90 | 2.875 | 17.02 | 0 | 1 | 4 | 4 |\n",
       "| 21.0 | 6 | 160.0 | 110 | 3.90 | 2.620 | 16.46 | 0 | 1 | 4 | 4 |\n",
       "| 16.4 | 8 | 275.8 | 180 | 3.07 | 4.070 | 17.40 | 0 | 0 | 3 | 3 |\n",
       "| 14.3 | 8 | 360.0 | 245 | 3.21 | 3.570 | 15.84 | 0 | 0 | 3 | 4 |\n",
       "| 18.7 | 8 | 360.0 | 175 | 3.15 | 3.440 | 17.02 | 0 | 0 | 3 | 2 |\n",
       "\n"
      ],
      "text/plain": [
       "   mpg  cyl disp  hp  drat wt    qsec  vs am gear carb\n",
       "1  24.4 4   146.7  62 3.69 3.190 20.00 1  0  4    2   \n",
       "2  22.8 4   140.8  95 3.92 3.150 22.90 1  0  4    2   \n",
       "3  22.8 4   108.0  93 3.85 2.320 18.61 1  1  4    1   \n",
       "4  18.1 6   225.0 105 2.76 3.460 20.22 1  0  3    1   \n",
       "5  19.2 6   167.6 123 3.92 3.440 18.30 1  0  4    4   \n",
       "6  17.8 6   167.6 123 3.92 3.440 18.90 1  0  4    4   \n",
       "7  21.4 6   258.0 110 3.08 3.215 19.44 1  0  3    1   \n",
       "8  21.0 6   160.0 110 3.90 2.875 17.02 0  1  4    4   \n",
       "9  21.0 6   160.0 110 3.90 2.620 16.46 0  1  4    4   \n",
       "10 16.4 8   275.8 180 3.07 4.070 17.40 0  0  3    3   \n",
       "11 14.3 8   360.0 245 3.21 3.570 15.84 0  0  3    4   \n",
       "12 18.7 8   360.0 175 3.15 3.440 17.02 0  0  3    2   "
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 3) Select the columns mpg and hp"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 12 × 2</caption>\n",
       "<thead>\n",
       "\t<tr><th></th><th scope=col>mpg</th><th scope=col>hp</th></tr>\n",
       "\t<tr><th></th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><th scope=row>Mazda RX4</th><td>21.0</td><td>110</td></tr>\n",
       "\t<tr><th scope=row>Mazda RX4 Wag</th><td>21.0</td><td>110</td></tr>\n",
       "\t<tr><th scope=row>Datsun 710</th><td>22.8</td><td> 93</td></tr>\n",
       "\t<tr><th scope=row>Hornet 4 Drive</th><td>21.4</td><td>110</td></tr>\n",
       "\t<tr><th scope=row>Hornet Sportabout</th><td>18.7</td><td>175</td></tr>\n",
       "\t<tr><th scope=row>Valiant</th><td>18.1</td><td>105</td></tr>\n",
       "\t<tr><th scope=row>Duster 360</th><td>14.3</td><td>245</td></tr>\n",
       "\t<tr><th scope=row>Merc 240D</th><td>24.4</td><td> 62</td></tr>\n",
       "\t<tr><th scope=row>Merc 230</th><td>22.8</td><td> 95</td></tr>\n",
       "\t<tr><th scope=row>Merc 280</th><td>19.2</td><td>123</td></tr>\n",
       "\t<tr><th scope=row>Merc 280C</th><td>17.8</td><td>123</td></tr>\n",
       "\t<tr><th scope=row>Merc 450SE</th><td>16.4</td><td>180</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 12 × 2\n",
       "\\begin{tabular}{r|ll}\n",
       "  & mpg & hp\\\\\n",
       "  & <dbl> & <dbl>\\\\\n",
       "\\hline\n",
       "\tMazda RX4 & 21.0 & 110\\\\\n",
       "\tMazda RX4 Wag & 21.0 & 110\\\\\n",
       "\tDatsun 710 & 22.8 &  93\\\\\n",
       "\tHornet 4 Drive & 21.4 & 110\\\\\n",
       "\tHornet Sportabout & 18.7 & 175\\\\\n",
       "\tValiant & 18.1 & 105\\\\\n",
       "\tDuster 360 & 14.3 & 245\\\\\n",
       "\tMerc 240D & 24.4 &  62\\\\\n",
       "\tMerc 230 & 22.8 &  95\\\\\n",
       "\tMerc 280 & 19.2 & 123\\\\\n",
       "\tMerc 280C & 17.8 & 123\\\\\n",
       "\tMerc 450SE & 16.4 & 180\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 12 × 2\n",
       "\n",
       "| <!--/--> | mpg &lt;dbl&gt; | hp &lt;dbl&gt; |\n",
       "|---|---|---|\n",
       "| Mazda RX4 | 21.0 | 110 |\n",
       "| Mazda RX4 Wag | 21.0 | 110 |\n",
       "| Datsun 710 | 22.8 |  93 |\n",
       "| Hornet 4 Drive | 21.4 | 110 |\n",
       "| Hornet Sportabout | 18.7 | 175 |\n",
       "| Valiant | 18.1 | 105 |\n",
       "| Duster 360 | 14.3 | 245 |\n",
       "| Merc 240D | 24.4 |  62 |\n",
       "| Merc 230 | 22.8 |  95 |\n",
       "| Merc 280 | 19.2 | 123 |\n",
       "| Merc 280C | 17.8 | 123 |\n",
       "| Merc 450SE | 16.4 | 180 |\n",
       "\n"
      ],
      "text/plain": [
       "                  mpg  hp \n",
       "Mazda RX4         21.0 110\n",
       "Mazda RX4 Wag     21.0 110\n",
       "Datsun 710        22.8  93\n",
       "Hornet 4 Drive    21.4 110\n",
       "Hornet Sportabout 18.7 175\n",
       "Valiant           18.1 105\n",
       "Duster 360        14.3 245\n",
       "Merc 240D         24.4  62\n",
       "Merc 230          22.8  95\n",
       "Merc 280          19.2 123\n",
       "Merc 280C         17.8 123\n",
       "Merc 450SE        16.4 180"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 4) Select the distinct values of the gear column"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 3 × 1</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>gear</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>4</td></tr>\n",
       "\t<tr><td>3</td></tr>\n",
       "\t<tr><td>5</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 3 × 1\n",
       "\\begin{tabular}{l}\n",
       " gear\\\\\n",
       " <dbl>\\\\\n",
       "\\hline\n",
       "\t 4\\\\\n",
       "\t 3\\\\\n",
       "\t 5\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 3 × 1\n",
       "\n",
       "| gear &lt;dbl&gt; |\n",
       "|---|\n",
       "| 4 |\n",
       "| 3 |\n",
       "| 5 |\n",
       "\n"
      ],
      "text/plain": [
       "  gear\n",
       "1 4   \n",
       "2 3   \n",
       "3 5   "
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 5) Create a new column called \"Performance\" which is calculated by hp divided by wt."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 12 × 12</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>mpg</th><th scope=col>cyl</th><th scope=col>disp</th><th scope=col>hp</th><th scope=col>drat</th><th scope=col>wt</th><th scope=col>qsec</th><th scope=col>vs</th><th scope=col>am</th><th scope=col>gear</th><th scope=col>carb</th><th scope=col>Performance</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160.0</td><td>110</td><td>3.90</td><td>2.620</td><td>16.46</td><td>0</td><td>1</td><td>4</td><td>4</td><td>41.98473</td></tr>\n",
       "\t<tr><td>21.0</td><td>6</td><td>160.0</td><td>110</td><td>3.90</td><td>2.875</td><td>17.02</td><td>0</td><td>1</td><td>4</td><td>4</td><td>38.26087</td></tr>\n",
       "\t<tr><td>22.8</td><td>4</td><td>108.0</td><td> 93</td><td>3.85</td><td>2.320</td><td>18.61</td><td>1</td><td>1</td><td>4</td><td>1</td><td>40.08621</td></tr>\n",
       "\t<tr><td>21.4</td><td>6</td><td>258.0</td><td>110</td><td>3.08</td><td>3.215</td><td>19.44</td><td>1</td><td>0</td><td>3</td><td>1</td><td>34.21462</td></tr>\n",
       "\t<tr><td>18.7</td><td>8</td><td>360.0</td><td>175</td><td>3.15</td><td>3.440</td><td>17.02</td><td>0</td><td>0</td><td>3</td><td>2</td><td>50.87209</td></tr>\n",
       "\t<tr><td>18.1</td><td>6</td><td>225.0</td><td>105</td><td>2.76</td><td>3.460</td><td>20.22</td><td>1</td><td>0</td><td>3</td><td>1</td><td>30.34682</td></tr>\n",
       "\t<tr><td>14.3</td><td>8</td><td>360.0</td><td>245</td><td>3.21</td><td>3.570</td><td>15.84</td><td>0</td><td>0</td><td>3</td><td>4</td><td>68.62745</td></tr>\n",
       "\t<tr><td>24.4</td><td>4</td><td>146.7</td><td> 62</td><td>3.69</td><td>3.190</td><td>20.00</td><td>1</td><td>0</td><td>4</td><td>2</td><td>19.43574</td></tr>\n",
       "\t<tr><td>22.8</td><td>4</td><td>140.8</td><td> 95</td><td>3.92</td><td>3.150</td><td>22.90</td><td>1</td><td>0</td><td>4</td><td>2</td><td>30.15873</td></tr>\n",
       "\t<tr><td>19.2</td><td>6</td><td>167.6</td><td>123</td><td>3.92</td><td>3.440</td><td>18.30</td><td>1</td><td>0</td><td>4</td><td>4</td><td>35.75581</td></tr>\n",
       "\t<tr><td>17.8</td><td>6</td><td>167.6</td><td>123</td><td>3.92</td><td>3.440</td><td>18.90</td><td>1</td><td>0</td><td>4</td><td>4</td><td>35.75581</td></tr>\n",
       "\t<tr><td>16.4</td><td>8</td><td>275.8</td><td>180</td><td>3.07</td><td>4.070</td><td>17.40</td><td>0</td><td>0</td><td>3</td><td>3</td><td>44.22604</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 12 × 12\n",
       "\\begin{tabular}{llllllllllll}\n",
       " mpg & cyl & disp & hp & drat & wt & qsec & vs & am & gear & carb & Performance\\\\\n",
       " <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl> & <dbl>\\\\\n",
       "\\hline\n",
       "\t 21.0 & 6 & 160.0 & 110 & 3.90 & 2.620 & 16.46 & 0 & 1 & 4 & 4 & 41.98473\\\\\n",
       "\t 21.0 & 6 & 160.0 & 110 & 3.90 & 2.875 & 17.02 & 0 & 1 & 4 & 4 & 38.26087\\\\\n",
       "\t 22.8 & 4 & 108.0 &  93 & 3.85 & 2.320 & 18.61 & 1 & 1 & 4 & 1 & 40.08621\\\\\n",
       "\t 21.4 & 6 & 258.0 & 110 & 3.08 & 3.215 & 19.44 & 1 & 0 & 3 & 1 & 34.21462\\\\\n",
       "\t 18.7 & 8 & 360.0 & 175 & 3.15 & 3.440 & 17.02 & 0 & 0 & 3 & 2 & 50.87209\\\\\n",
       "\t 18.1 & 6 & 225.0 & 105 & 2.76 & 3.460 & 20.22 & 1 & 0 & 3 & 1 & 30.34682\\\\\n",
       "\t 14.3 & 8 & 360.0 & 245 & 3.21 & 3.570 & 15.84 & 0 & 0 & 3 & 4 & 68.62745\\\\\n",
       "\t 24.4 & 4 & 146.7 &  62 & 3.69 & 3.190 & 20.00 & 1 & 0 & 4 & 2 & 19.43574\\\\\n",
       "\t 22.8 & 4 & 140.8 &  95 & 3.92 & 3.150 & 22.90 & 1 & 0 & 4 & 2 & 30.15873\\\\\n",
       "\t 19.2 & 6 & 167.6 & 123 & 3.92 & 3.440 & 18.30 & 1 & 0 & 4 & 4 & 35.75581\\\\\n",
       "\t 17.8 & 6 & 167.6 & 123 & 3.92 & 3.440 & 18.90 & 1 & 0 & 4 & 4 & 35.75581\\\\\n",
       "\t 16.4 & 8 & 275.8 & 180 & 3.07 & 4.070 & 17.40 & 0 & 0 & 3 & 3 & 44.22604\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 12 × 12\n",
       "\n",
       "| mpg &lt;dbl&gt; | cyl &lt;dbl&gt; | disp &lt;dbl&gt; | hp &lt;dbl&gt; | drat &lt;dbl&gt; | wt &lt;dbl&gt; | qsec &lt;dbl&gt; | vs &lt;dbl&gt; | am &lt;dbl&gt; | gear &lt;dbl&gt; | carb &lt;dbl&gt; | Performance &lt;dbl&gt; |\n",
       "|---|---|---|---|---|---|---|---|---|---|---|---|\n",
       "| 21.0 | 6 | 160.0 | 110 | 3.90 | 2.620 | 16.46 | 0 | 1 | 4 | 4 | 41.98473 |\n",
       "| 21.0 | 6 | 160.0 | 110 | 3.90 | 2.875 | 17.02 | 0 | 1 | 4 | 4 | 38.26087 |\n",
       "| 22.8 | 4 | 108.0 |  93 | 3.85 | 2.320 | 18.61 | 1 | 1 | 4 | 1 | 40.08621 |\n",
       "| 21.4 | 6 | 258.0 | 110 | 3.08 | 3.215 | 19.44 | 1 | 0 | 3 | 1 | 34.21462 |\n",
       "| 18.7 | 8 | 360.0 | 175 | 3.15 | 3.440 | 17.02 | 0 | 0 | 3 | 2 | 50.87209 |\n",
       "| 18.1 | 6 | 225.0 | 105 | 2.76 | 3.460 | 20.22 | 1 | 0 | 3 | 1 | 30.34682 |\n",
       "| 14.3 | 8 | 360.0 | 245 | 3.21 | 3.570 | 15.84 | 0 | 0 | 3 | 4 | 68.62745 |\n",
       "| 24.4 | 4 | 146.7 |  62 | 3.69 | 3.190 | 20.00 | 1 | 0 | 4 | 2 | 19.43574 |\n",
       "| 22.8 | 4 | 140.8 |  95 | 3.92 | 3.150 | 22.90 | 1 | 0 | 4 | 2 | 30.15873 |\n",
       "| 19.2 | 6 | 167.6 | 123 | 3.92 | 3.440 | 18.30 | 1 | 0 | 4 | 4 | 35.75581 |\n",
       "| 17.8 | 6 | 167.6 | 123 | 3.92 | 3.440 | 18.90 | 1 | 0 | 4 | 4 | 35.75581 |\n",
       "| 16.4 | 8 | 275.8 | 180 | 3.07 | 4.070 | 17.40 | 0 | 0 | 3 | 3 | 44.22604 |\n",
       "\n"
      ],
      "text/plain": [
       "   mpg  cyl disp  hp  drat wt    qsec  vs am gear carb Performance\n",
       "1  21.0 6   160.0 110 3.90 2.620 16.46 0  1  4    4    41.98473   \n",
       "2  21.0 6   160.0 110 3.90 2.875 17.02 0  1  4    4    38.26087   \n",
       "3  22.8 4   108.0  93 3.85 2.320 18.61 1  1  4    1    40.08621   \n",
       "4  21.4 6   258.0 110 3.08 3.215 19.44 1  0  3    1    34.21462   \n",
       "5  18.7 8   360.0 175 3.15 3.440 17.02 0  0  3    2    50.87209   \n",
       "6  18.1 6   225.0 105 2.76 3.460 20.22 1  0  3    1    30.34682   \n",
       "7  14.3 8   360.0 245 3.21 3.570 15.84 0  0  3    4    68.62745   \n",
       "8  24.4 4   146.7  62 3.69 3.190 20.00 1  0  4    2    19.43574   \n",
       "9  22.8 4   140.8  95 3.92 3.150 22.90 1  0  4    2    30.15873   \n",
       "10 19.2 6   167.6 123 3.92 3.440 18.30 1  0  4    4    35.75581   \n",
       "11 17.8 6   167.6 123 3.92 3.440 18.90 1  0  4    4    35.75581   \n",
       "12 16.4 8   275.8 180 3.07 4.070 17.40 0  0  3    3    44.22604   "
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 6) Find the mean mpg value"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 1 × 1</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>avg_mpg</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>20.09062</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 1 × 1\n",
       "\\begin{tabular}{l}\n",
       " avg\\_mpg\\\\\n",
       " <dbl>\\\\\n",
       "\\hline\n",
       "\t 20.09062\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 1 × 1\n",
       "\n",
       "| avg_mpg &lt;dbl&gt; |\n",
       "|---|\n",
       "| 20.09062 |\n",
       "\n"
      ],
      "text/plain": [
       "  avg_mpg \n",
       "1 20.09062"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### 7) Use pipe operators to get the mean of hp value for cars with 6 cylinders"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<table>\n",
       "<caption>A data.frame: 1 × 1</caption>\n",
       "<thead>\n",
       "\t<tr><th scope=col>avg_hp</th></tr>\n",
       "\t<tr><th scope=col>&lt;dbl&gt;</th></tr>\n",
       "</thead>\n",
       "<tbody>\n",
       "\t<tr><td>122.2857</td></tr>\n",
       "</tbody>\n",
       "</table>\n"
      ],
      "text/latex": [
       "A data.frame: 1 × 1\n",
       "\\begin{tabular}{l}\n",
       " avg\\_hp\\\\\n",
       " <dbl>\\\\\n",
       "\\hline\n",
       "\t 122.2857\\\\\n",
       "\\end{tabular}\n"
      ],
      "text/markdown": [
       "\n",
       "A data.frame: 1 × 1\n",
       "\n",
       "| avg_hp &lt;dbl&gt; |\n",
       "|---|\n",
       "| 122.2857 |\n",
       "\n"
      ],
      "text/plain": [
       "  avg_hp  \n",
       "1 122.2857"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Great job!"
   ]
  }
 ],
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