Can some show me how to do these kinds of word problems please?

Question

Mark drove 250 mi to visit Sandra. Returning by a shorten route, he found that the trip was only 225 mi, but traffic slowed his speed by 5 miles. If the two trips took exactly the same time, what was his rate on the return trip?

Answer 1

You need to ignore the wording and concentrate on facts.

distances are 250 & 225.  Time was the same, so ignore it.  The variable is speed, so we call it x

This gives us the formula, which we solve for x:

250x-225(x-5) = 0

250x-225x-1125 = 0

25x = 1125

x = 45

This gives us the original trip speed.  The return trip was 5 mph slower, so it is 40 mph.

Answer 2

First, I need to know how fast Mark was going (MPH)? I can not answer the question without that info.