Question 1046513
He can't have 4, 5, or 6 quarters because that
doesn't leave enough nickels for 23 coins
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6 quarters + 1 nickel = $1.55
5 quarters + 6 nickels = $1.55
4 quarters + 11 nickels = $1.55
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So far I'm up to 15 coins maximum
3 quarters = .75
16 nickels = .80
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$1.55 total
That's still only 19 coins
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2 quarters = .50
21 nickels = 1.05 
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$1.55 total
This works, but I don't have any dimes
so, 2 quarters won't work
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1 quarter = .25
6 dimes = .60
14 nickels = .70
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$1.55 total -only 21 coins
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1 quarter = .25
5 dimes = .50
16 nickels = .80
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$1.55 total -but only 22 coins
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1 quarter = .25
4 dimes = .40
18 nickels = .90
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$$1.55 total and 23 coins
This is ( one of the ) answers