Question 55377
Write an equation for each phrase/statement
:
A bank contains 36 nickels, dimes, and quarters.
n + d + q = 36
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There are 4 more dimes than quarters
d = q + 4
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and twice as many nickels as quarters.
n = 2q
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 How many of each coin are in the bank?
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Notice that if we substitute (q+4) for d, and 2q for n in the 1st equation, we only have one unknown to deal with, "q":
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2q + (q+4) + q = 36
2q + q + 4 + q = 36
            4q = 36 - 4
            4q = 32
             q = 32/4
q = 8 quarters
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Now I am sure you can find the number of nickels and dimes by substituting 8 for q in the above equations.  Then check your solutions in the 1st equation