Hello, ((ECHO))!

I get the same answer is behemoth and Jhevon . . .

A swimming pool is 22 ft wide and 60 ft long.

It is 2 ft deep at the shallow end, and 10 ft deep at the other end.

If the pool is being filled with water at a rate of 0.8 ft³/min,

how fast is the water level rising when the depth at the deepest point is 7 ft? Code:

60
- * - - - - - - - - - - - - - - - - - - - - *
: | |
2 | | 2
: | 60 |
- A + - - - - - - - - - - - - - - - - - - - - * B
: | *
: | x *
: C +-----------------------* D
8 |:::::::::::::::::*
: |h :::::::::*
: |:::::*
- E *

Since , we have: . .**[1]**

. . Hence: . . **[2]**

The volume of water is: .

. . Then: . . **[3]**

When , [1] gives us: .

Substitute into [3]: .

Hence: .

Therefore: . ft/min.