If a rectangle has a width of 42 inches and an area of 1638, how many rectangles of the same size would reach a length of 390 inches?
The rectangle has a length of 1638 in/ 42in = <<1638/42=39>>39 in.
The number of rectangles required to reach 390 inches is 390/39 = <<390/39=10>>10 rectangles.
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