Golden Ratio question? Please help^^

I reviewed over the lesson but I still cant find the answer to this question. Can someone help me?

The local community park is designing a pool using the Golden Ratio. If the pool is 110 feet wide, about how long should it be?
A 100 feet
B 120 feet
C 150 feet
D 180 feet

110/x = 1/1.618
x = 177.983...

D

The golden ratio is approximately 1 : 1.62

Then, 110 x 1.62 = 178.2, and that means something very close to 180 feet.
I'd answer D.