Answer: $8
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Work Shown:
(5 oranges)/(2 dollars) = (20 oranges)/(x dollars)
5/2 = 20/x
5x = 2*20 .... cross multiply
5x = 40
x = 40/5 .... dividing both sides by 5
x = 8
20 oranges cost $8
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Another way to approach the problem is to note that the jump from "5 oranges" to "20 oranges" is "times 4".
5*4 = 20
So we'll apply the "times 4" operation to the old cost of $2 to get the new cost being 2*4 = 8 dollars
