Water lilies
There are some water lilies in a lake. The area that they cover doubles in size every day. After 17 days the whole lake is covered. How long did it take them to cover half the lake?
Age
11 to 14
Challenge level
Problem
Image
There are some water lilies in a lake.
The area that they cover doubles in size every day.
After 17 days the whole lake is covered with water lilies.
How long did it take them to cover half the lake?
Getting Started
It might help to imagine that each water lily covers a certain area of the lake and notice what happens as they double in size.
Teachers' Resources
Looks more difficult than it is!