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

2 Answers
Jan 22, 2017

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

Jan 22, 2017

#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