Amanda has a total of 80 nickels and quarters. The total value of the change is $7.60. How many nickels does she have?

She has 62 nickels and 18 quarters.

You can find this by setting up the following system of equations:

x + y = 80 (total number of coins)

5x + 25y = 760 (total number of cents)

Then you can mutliply the first equation by - 5 to get the x values to cancel out. You can then solve this for y.