Question 1021560
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A collection of quarters and nickels is worth $3.80. There are 24 coins in all. How many of each are there?
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<pre>
 n +   q =  24,    (1)   (counting coins, nickels n and quarters q)
5n + 25q = 380.    (2)   (counting money in cents)

Express n = 24-q from (1) and substitute it into (2). You will get a single equation for q

5(24-q) + 25q = 380.

Simplify and solve it:

120 - 5q + 25q = 380,

20q = 380-120

20q = 260,

q = {{{260/20}}} = 13.

<U>Answer</U>. 13 quarters and 24-13 = 11 nickels.

<U>Check</U>.  11*5 + 13*25 = 380.
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