Question 1104494
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D + Q = 20.

25D + 10Q = 10D + 25Q + 90


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D + Q = 20,

15D - 15Q = 90


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D + Q = 20
D - Q =  6
----------------Add the equations


2D = 26  ====>  D = 13.


<U>Answer</U>.  13 dimes and (20-13) = 7 quarters.
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