Please help answer number 18.

First of all, we need to know that:

From the problem, we know that:

Converting gallon to quarts:

For Angela:

For Ryou:

Number of blue walls:

So we can paint 3 walls.

Number of white walls:

So we can paint just one wall.

For blue paint:

We can solve this by a rule of three as follows:

For white paint:

We can solve this by a rule of three as follows:

-14

step-by-step explanation:

2x2 – 2(x+4)

=2x2-2（5+4）

=4-2×9

=4-18

=-14

step-by-step explanation:

mean or average is 40.6