Exercise 29 Page 784

We are given that Madison wants to know how many pints of yellow and blue paint she will need to color the tower and the roof, keeping in mind that each need $3$ coats of paint. Let's take a look at the given picture.

First we can evaluate the area of a triangle. Let's recall the formula for the area of this figure. In this formula $b$ is the base of a triangle and $h$ is the corresponding height. To find the area of the yellow triangle we will substitute $5$ for $b$ and $6$ for $h.$ The area of the triangle is $15$ ft${}^2.$ However, as we need $3$ coats of paint, we will multiply this result by $3.$ Then we will divide it by $80,$ as one pint of paint covers $80$ square feet. Finally we will round the result to the nearest integer that is not less than this number. Madison needs $1$ pint of yellow paint. Now we will evaluate the area of a tower that is a rectangle. Recall that the area of a rectangle is the product of its dimensions. Therefore, the area of the blue tower will be the product of $5$ and $12.$ As we did with the area of a triangle, we should multiply $60$ ft${}^2$ by the number of coats of paint, $3,$ and divide it by $80$ square feet. Again, we will round the result to the nearest integer that is not less than this number. Madison needs $3$ pints of blue paint.