Answer: $142.80
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Explanation:
To get this answer, we double the 71.40 to get 142.80
You can think of it like an equation and we multiply both sides by 2
4 jeans = 71.40 dollars
2*(4 jeans) = 2*(71.40 dollars)
8 jeans = 142.80 dollars
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Or you could solve it like this
(4 jeans)/(71.40 dollars) = (8 jeans)/(x dollars)
4/71.40 = 8/x
4x = 71.40*8
4x = 571.2
x = 571.2/4
x = 142.80
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Yet another way to solve is to first find the unit rate
4 jeans cost 71.40, so that must mean 1 pair of jeans cost 71.40/4 = 17.85 dollars. This is the unit rate since "unit" means "one". It's the price per pair of jeans.
Multiply that by 8 to find out how much 8 pairs will cost, and we get 17.85*8 = 142.80
