2 times as many dimes as quarters and they have a combined value of 180 cents, how many of each coin

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2 times as many dimes as quarters and they have a combined value of 180 cents, how many of each coin does he have?

Let d be the number of dimes. Let q be the number of quarters. We're given two equations:

1. d = 2q
2. 0.1d + 0.25q = 180

Substitute (1) into (2):
0.1(2q) + 0.25q = 180
0.2q + 0.25q = 180

Typing this equation into the search engine, we get:
q = 400

Now substitute q = 400 into equation 1:
d = 2(400)
d = 800