Question

Sierra applies a coat of epoxy paint to the four sides and floor of a rectangular swimming pool. The pool is 4 feet deep, 18 feet long, and 12 feet wide. One gallon of paint covers 155 square feet. Does sierra use 3 gallons of paint or 4 gallons of paint? Explain

Answer 1

Answer:

4 gallons of paint

Step-by-step explanation:

We solve using the formula for surface area of rectangular prism.

A=2(wl+hl+hw)

Where:

w = Width

h = Height

l = Length

The pool is 4 feet deep, 18 feet long, and 12 feet wide.

Hence,

=2 × (12 × 18 + 4 × 18 + 4 ×12)

=672 square feet

One gallon of paint covers 155 square feet.

Hence,

155 square feet = 1 gallon of paint

672 square feet = x

Cross Multiply

155 square feet × x = 672 square feet × 1 gallon of paint

x = 672 square feet × 1 gallon of paint/ 155 square feet

x = 4.335483871 gallons of paint

Therefore, based on the calculation above, approximately to the nearest whole number, Sierra uses 4 gallons of paint