The area covered by water lilies in a pond you own doubles in size every day. If allowed to grow the plants would cover the entire pond surface in 30 days. You had decided to do nothing until the pond is ½ covered.

Question

a. On what day will the pond be ½ covered?
b. How long do you have before you must act or have your pond covered with the plants?

Answer 1

a. The pond will be 1/2 covered on the 29th day.

Answer 2

i got that but i was not sure about b)b. How long do you have before you must act or have your pond covered with the plants?

Answer 3

30 - 29 = ?

Answer 4

I don't know either could you help me today? like now