SOLUTION: Nina saved $78.00 in March. That was 20% more than she saved in Feb. How much did Nina save in Feb? How to solve this?

Algebra ->  Equations -> SOLUTION: Nina saved $78.00 in March. That was 20% more than she saved in Feb. How much did Nina save in Feb? How to solve this?       Log On


   

Question 883587: Nina saved $78.00 in March. That was 20% more than she saved in Feb. How much did Nina save in Feb?
How to solve this?

Answer by montecristo73(8) About Me  (Show Source):
You can put this solution on YOUR website!
The problem says that 78 is 20% more than what Nina saved in Feb.
Since we do not know what is the quantity she saved in Feb let's call that x.
So, turning this into an equation we have...
78 = x + x(.20)
Why x + x(.20)? Because the problem is basically telling us that the sum of what she saved in Feb (x) and 20% of x will result in 78. To find 20% of x we multiply x(.20)
Now...
78 = x + .20x
Let's multiply both sides by 100 to get rid of that nasty decimal.
7800 = 100x + 20x
7800 = 120x
Now it's just a matter of isolating x. We divide each side by 120 which gives us...
x = 7800/120
x = 65
Verify now...
65 (what she saved in Feb) plus 20% percent of that should give you 78.
65 + 65(.20)
= 65 + 13
=78
Voila!