# Question b14cd

Feb 18, 2017

It takes 8 hours to travel 128 miles

#### Explanation:

Using ratio

miles per hour $\to \left(\text{distance")/("time}\right) = \frac{15}{1}$

But the target is 120 miles so we need to change the 15 into 120.

Multiply by 1 and you do not change the value. However, 1 comes in many forms so you can change the way something looks without changing its true value.

("miles")/("hours")->color(green)(15/1color(red)(xx1) = 15/1color(red)(xx8/8)" "=" "120/8#

So it takes 8 hours to travel 128 miles
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Note that $15 \div 1 = 15 = 120 \div 8$