Answer:
10
Explanation:
we can solve this using basic algebra
We set up the equation using the info that each video costs $5 and that we but 12 of them
12(1 * 5) + x = 70
(Please note: 1x = x)
12(5) + x = 70
60 + x = 70
60 - 60 + x = 70 - 60
x = 10
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