Question 1070015
$4.50 could be made with 18 quarters, but you want 28 total coins.


One quarter, $0.25, can be split into 1 nickel and 2 dimes.  Each such splitting will add 2 coins to the combination of coins.


17 q + 1 n + 2 d = 4.50, count of 20 coins;

16 q + 2 n + 4 d = 4.50, count of 22 coins;

Keep going like this and find:
13 q +5 n + 10 d = 4.50, 28 coins.



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COMBINATION:
13 quarters
5 nickels
10 dimes
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