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This problem trains for: Math Kangaroo 5-6, Math Kangaroo 7-8, SAT-I, AMC-8, GMAT.
In Harpagon's purse, there are q quarters, d dimes and n nickels. Which of the following combinations of coins add up to the same total value?
(character from Molière's "The Miser")
We have to evaluate all the amounts that get added or subtracted for each set of coins:
For q+5, d-2, n-3 we add 5 quarters which is 5*25=125 cents and subtract 2 dimes (20 cents) and 3 nickels (15 cents). We add more than we subtract, therefore we do not conserve the total amount.
For q-2, d+4, n+1 we subtract 2 quarters which is 50 cents and add 4 dimes (40 cents) and 1 nickel (5 cents). We add less than we subtract, therefore we do not conserve the total amount.
For q-3, d+6, n+3 we subtract 3 quarters which is 75 cents and add 6 dimes (60 cents) and 3 nickels (15 cents). We add the same amount as we subtract, therefore we do conserve the total amount. This is the correct answer.