Question 1063877
Same problem, different numbers.
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Mary has 30 nickels and dimes totaling $2.40. How many of each does she have
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n + d = 30 --------- # of coins
5n + 10d = 240 --------Value of coins
--> n + 2d = 48 ---------- 2nd eqn divided by 5
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n + d = 30 --------- # of coins
n + 2d = 48
------------ Subtract
-d = -18
--> 18 dimes
12 nickels