A box contains 140 dimes and nickels.

The total value is $11.15. How many dimes and nickels are there?

Need the help finding the formula.

1 answer

Let d = # dimes and
n = # nickels.
Set up two equations from the problem.
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d + n = 140
0.10d + 0.05n = 11.15
Solve for d and n.
Post your work if you get stuck. I suggest you multiply equation 1 by -0.05 and add it to equation 2, then solve.