Question

Kenneth drove 194.3 miles in 3 7/20 hours. What was his average speed?

Answer 1

58 miles per hour

Explanation:

In this case average means; what is the one value that if multiplied by the total time (in hours) will give 194.3 miles.

We do this by ending up with the distance traveled in 1 hour (unit time)

Using ratio `color(brown)(->" miles per hour "-> ("miles")/("hours") ->m/h -> 194.3/(3 7/20))`

So we need to change the `3 7/20` into 1

Divide top and bottom by `3 7/20`

`m/h-=(194.3-: 3 7/20)/(3 7/20-: 3 7/20)`

`m/h = (194-:3 7/20)/1`

`m/h = 58/1`

So the average speed is 58 miles in 1 hour `->`58 miles per hour

Answer 2

`58 mph`

Explanation:

194.3miles in `3 7/20`hours

= 194.3 miles in`67/20=3.35 hours`

`3.35hours=194.3`miles

`1 hour=1/3.35 xx 194.3/1=58mph`

check:

`58mph xx 3.35hours=194.3`miles