Question 1071754
 emma has 4 more quarters than nickels. the total value of her quarters and nickels is $3.10. In all, what is the number of nickels that emma has? 
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q = n + 4
25q + 5n = 310 cents
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Substitute for "q" and solve for "n"::
25(n+4) + 5n = 310
25n + 100 + 5n = 310
30n = 210
n = 7 (# of nickels)
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Cheers,
Stan H.
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