Question 1131033
Jamil always throws loose change into a pencil holder on his desk and takes it out every two weeks. This time it is all nickels and dimes. There are twice as many dimes as nickels, and the value of the dimes is $ 0.90 more than the value of the nickels. How many nickels does Jamil have? 
Equations:
d = 2n
10d - 5n = 90 cents
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Substitute for "d" and solve for "n"::
10(2n) - 5n = 90
15n = 90
n = 6 (# of nickels)
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Cheers,
Stan H.
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