inwosu wrote:

One hour after Yolanda started walking from X to Y, a distance of 45 miles, Bob started walking along the same road from Y to X. If Yolanda's walking rate was 3 miles per hour and Bob's was 4 miles per hour, how many miles had Bob walked when they met?

a)24

b)23

c)22

d)21

e)19.5

A.

In one hour, Yolanda walked: 3*1 = 3 miles

Therefore, the distance when Yolanda and Bob started at the same time is: 45-3 = 42 miles

Since they are walking toward each other, find out how long it takes for both of them to meet by adding speed:

4+3 = 7mph

Therefore, it will take them: (1/7)*42 = 6 hours to meet

In 6 hours, Bob walked: 6*4 = 24