Pearson Algebra 1 Common Core, 2011
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Pearson Algebra 1 Common Core, 2011 View details
8. Proportions and Similar Figures
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Exercise 21 Page 135

An architect is using the blueprint shown below where the side length of each grid square represents 12 inches.

We are asked if it would be possible to wheel a laundry cart that is 3 12 feet wide through the room from the doorway at the left to the doorway at the right. We can start by finding the scale of the blueprint. Blueprint's scale &= $1$ Grid side length/$12$ inches

Notice that the narrowest part through which the laundry cart would have to go is 3 grid side lengths.

As the blueprint is drawn to scale, all the lengths will keep the same ratio with their actual corresponding lengths l . Side length/Actual length &= $3$ Side lengths/Actual corresponding length 1/12 &= 3/l We can now solve for the narrowest length l.
1/12 = 3/l
1 * l = 12 * 3
l = 36
Hence, the actual measurement at the narrowest part would be 36 inches. Recall that the laundry cart is 3 12 feet wide. Let's convert the length of the laundry cart from feet to inches, multiplying by a conversion factor. 3 12 ft = 3.5 ft ( 12 in/1 ft ) = 42 in Since the narrowest part measures at only 36 inches, the laundry cart will not fit. It will not be possible to wheel it through the room from doorway to doorway.