In a Lake, there is a patch of lily pads. Every day, the patch doubles in size. It takes 37 days for the patch to cover the entire lake, how many days would it take the patch to cover half of the lake?
Choose the correct choice from the following answers:
A) 36
B) 2 ^ 4 * 3
C) 24
D) 38
E) 47

Rationale: "working backward from the day it ' s covered : day 37 : fully covered day 36 : half covered so 36 days answer : a"
Answer: A