A bag of quarters and nickels is worth $8.30. There are two less than three times as many quarters a

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A bag of quarters and nickels is worth $8.30. There are two less than three times as many quarters as nickels. How many of the coins must be quarters?

Assumptions and givens:

• Let the number of quarters be q
• Let the number of nickels be n

We have two equations:

1. 0.05n + 0.25q = 8.30
2. n = 3q - 2 (Two less than Three times)

Plug in equation (2) into equation (1) for q to solve this system of equations:
0.05(3q - 2) + 0.25q = 8.30

To solve this equation for q, we type it in our search engine and we get:
q = 21