word problem

[franklin91]

A pilot flew a jet from city A to city B, a distance of 1500 mi. On the return trip, the average speed was 20% faster than the outbound speed. The round-trip took 3 h 40 min. What was the speed from city A to city B?

I dont know how to work word problems....can someone describe the steps to solve this

 

[mmm4444bot]

d = r*t

Therefore, t = d/r

This means that the number of hours t equals the ratio distance over rate.

They give the distance: 1500 miles

Flying from A to B, the rate is R miles per hour

Therefore, the time flying from A to B is 1500/R hours.

Flying from B to A, the rate is 20% more: R + 0.2R

Therefore, the time flying from B to A is 1500/(R + 0.2R) hours

These two times total 3 hours 40 minutes.

40 minutes is 40/60 hours, or 4/6 hours, or 2/3 hours

3 2/3 is 11/3 hours

Therefore, the equation to solve is:

1500/R + 1500/(R + 0.2R) = 11/3

 

[franklin91]

thank you for the help