At the park there is a pool shaped like a circle with radius
11yd
. A ring-shaped path goes around the pool. Its width is
5yd
.We are going to give a new layer of coating to the path. If one gallon of coating can cover
6yd2
, how many gallons of coating do we need? Note that coating comes only by the gallon, so the number of gallons must be a whole number. (Use the value
3.14 for π.)

Question

At the park there is a pool shaped like a circle with radius 
11yd
. A ring-shaped path goes around the pool. Its width is 
5yd
.We are going to give a new layer of coating to the path. If one gallon of coating can cover 
6yd2
, how many gallons of coating do we need? Note that coating comes only by the gallon, so the number of gallons must be a whole number. (Use the value 
3.14 for π.)

anonymous · Answer

@KendrickLamar2014

kendricklamar2014 · Answer

Note that coating comes only by the gallon, so the number of gallons must be a whole number. 
:
With a 5' path around the pool the overall radius (including the path)
11 + 5 = 16 ft

Path Area (pa) = Overall Area - Pool Area

kendricklamar2014 · Answer

pa = (3.14*16^2) - (3.14*11^2) = 
pa = 803.84 - 379.94 = 
pa = 423.9 sq/yds

kendricklamar2014 · Answer

To find the amount of coating needed: 423.9/6 = 70.65 = 71

anonymous · Answer

oh ok got it! I knew part of it but the the gallons part messed me up

anonymous · Answer

thank you!

kendricklamar2014 · Answer

You're Welcome :)