, write equivalent ratios that represent the situation and solve. 12. Angela pays $120 for 4 piano lessons. How much does she pay for 8 piano lessons?

She pays $240 for 8 lessons.

Step-by-step explanation:

We need to set up equivalent ratios so we can cross-multiply and solve for x, the amount Angela pays for 8 lessons. Make sure to have both the costs in the numerator, and the number of lessons in the denominator. If you mix it up, this won't work.

Cross-multiply:

120*8 = 4x

Solve for x:

960 = 4x

960/4 = x

x = $240

Simply multiply 2 1/4 x 3 1/2  = 7 7/8 gallons of water or 7.875

In 1 minute 2 1/4 gallons
In 2 minutes  4 1/2 gallons  (2 1/4 x 2)
In 3 minutes   6  3/4   (2 1/4 x 3)
In the remaining 1/2 minute it will pour out 1  1/8  gallons   (2 1/4 ÷ 2)
Add that to the 6  3/4 and you will also get 7  7/8 gallons