Question

10. The parking lot at the local Dairy Queen store has 4 cylindrical posts in front of the store as shown below. The top and sides of these posts need to be painted bright red. The diameter of the base of each post is 3 feet, and each post is 4 feet high. How many square feet must be painted on the four posts? A. 179.07 ft? C. 263.90 ft? B. 65.97 ft? D. 44.77 ft?

Answer 1

EXPLANATION

If we need to paint the top and sides of these posts and the radius=d/2= 3/2=1.5 ft, and the height is equal to h=4= ft, the area will be:

$\text{Area}_{cylinder}=Area\text{ of top + Area of side}$

Replacing terms:

$\text{Area}_{\text{cylinder}}=\pi\cdot r^2+2\cdot\pi\cdot r\cdot h$

Substituting terms:

$\text{Area }=\pi\cdot(1.5)^2+2\cdot\pi\cdot(1.5)\cdot4$

Multiplying numbers:

$\text{ Area}=\frac{9}{4}\pi+12\cdot\pi$

Adding like terms:

$\text{Area}=\frac{57}{4}\pi=14.25\pi=44.77ft^2$

The answer is the option D: 44.77ft^2