Question

A salesman drove from his home to a nearby city at an average speed of 40 mi/h. He returned home at an average speed of 50 mi/h. What was his average speed for the entire trip?

Answer 1

Answer:

44.44 mph

Step-by-step explanation:

$speed = \frac{distance}{time} = \frac{distanceTo + distanceFrom}{time1 + time2} = \frac{2d}{\frac{d}{40} + \frac{d}{50} }$

= $\frac{2d}{\frac{5d + 4d}{200} } = \frac{2d}{\frac{9d}{200} }$

= 2d * $\frac{200}{9d}$

= 400 / 9

= 44.44

Answer 2

Answer:

44.4 miles per hour

Step-by-step explanation:

d = the distance between cities

t 1= the time from home to the city

t 1 = the time . from the city to home

2d/t1 + t2 = 2d/ d/40 + d/50

=2d/5d+4d =2d/9d

divide both sides by 200

=2d * 200/9d =400/9

= 44.4