Joel bought 2 notebooks, 3 pencils, and 6 files for $12.70. The cost of 1 pencil and 2 files is $4. What is the cost of 1 notebook?
If 1 pencil and 2 files = 4
Then 3 pencils and 6 files are three times 4 = 12
So....2 notebooks must cost 12.70 - 12 = .70
So.....1 notebook = .35 (35 cents)
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