If the question concerned the number of combinations of three different coins, the answer is 231 = 7. If the coins are a,b,and c, the combinations are. a, b, c, ab, ac, bc, abc.
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2 Nickels and 2 Dimes
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1 nickel weighs 5 grams. 20 nickels would weigh 100 grams. 1 penny weighs
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Only 2 solutions (1) 45 pennies 2 nickels 2 dimes 1 quarter (2) 1 quarter and 40 pennies 8 nickels 2 dimes 1a + 5b + 10c + 25d + 50e = 100 a + b + c + d + e = 50 using a = 50
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