Answer: 3 inches
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Step-by-step explanation:
The problem states that 1 inch on paper corresponds to 2 miles in real life, hence the 1 inch = 2 miles.
Multiply both sides by 3 so we turn that "2 miles" into "6 miles"
1 inch = 2 miles
3*(1 inch) = 3*(2 miles)
3 inches = 6 miles
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We could also solve like this
(1 inch)/(2 miles) = (x inches)/(6 miles)
1/2 = x/6
1*6 = 2*x ... cross multiply
6 = 2x
2x = 6
x = 6/2
x = 3
3 inches on paper correspond to 6 miles in real life.