Question 936304
Mark has 45 cents in dimes and nickels. He has 3 more nickels than dimes. How many of each type of coin does Mark have? Write a system of equations, then solve. 
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Another method:
Put the "3 more nickels" to the side.
What's left is an equal # of Ns and Ds worth 30 cents.
Each pair is 15 cents.
30/15 = 2 pairs
--> 2 dimes and 5 nickels