McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
7. Scale Drawings and Models
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Exercise 13 Page 603

First, measure the distance on the map. Then, create a proportion to evaluate the actual distance.

≈2.7 h

Practice makes perfect
We are given that the scale of a map is 1inch: 200miles. Our first step will be to find the actual distance between Valdosta, Georgia, and Daytona, Florida. To do this we will can create a proportion. 1/200=distance on map/actual distance After measuring the distance using a ruler, we can see that the cities are 78 inches apart on the map. Let's substitute this value into the proportion. Let x represent the actual distance. 1/200=78/x Now we will solve the above proportion for x using cross multiplication.
1/200=78/x
1* x=200*7/8
Solve for x
x=200*7/8
x=200*7/8
x=1400/8
x=175
The distance between these two cities is 175 miles. Next, we are asked to evaluate how long would it take to drive from Valdosta to Daytona if we travel 65 miles per hour. To do this, we will recall the speed formula and solve it for time. Speed=Distance/Time ⇓ Time=Distance/Speed Finally we will substitute 65 miles per hour for speed and 175 miles for distance. Let t be the time.
Time=Distance/Speed
t=175/65
t=2.6923...
t≈2.7
It would take approximately 2.7 hours to drive from Valdosta to Daytona.