## Basic College Mathematics (10th Edition)

$72$ feet (ft.) of lumber
To find the amount of lumber we will find the distance around the entire patio, we will add the three sides (18, 30, 24) $18 + 30 + 24$ Start at the right of each number and add the ones digits $8 + 0 + 4 = 12$ ones Regroup the $12$ ones as $1$ ten and $2$ ones Write the $2$ ones in the ones column. Write the $1$ ten in the tens column Add the tens column next including the regrouped $1$ $1 + 1 + 3 + 2 = 7$ tens Write the $7$ tens in the tens column. The sum of the three numbers is $72$ The distance is $72$ feet (ft).