Posted by **Emme** on Sunday, January 20, 2013 at 2:10am.

A jet flew from Tokyo to Bangkok, a distance of 4800km. On the return trip the speed was decreased by 200km/h. If the difference times of the fights was 2 hours, what was the speed from Bangkok to Tokyo.

- Math -
**Reiny**, Sunday, January 20, 2013 at 8:40am
time for 1st flight = 4800/x

time for return flight = 4800/(x-200)

4800/(x-200) - 4800/x = 2

multiply by x(x-200)

4800x - 4800(x-200) = 2x(x-200)

960000 = 2x^2 - 400x

x^2 - 200x - 480000=0

(x - 800)(x + 600) = 0

x = 800 or x = -600 , the negative speed makes no sense

so x = 800 km/h

check:

1st flight = 4800/800 = 6 hrs

2nd flight = 4800/600 = 8 hrs

difference is 2 hours, YEahh!

## Answer This Question

## Related Questions

- math - A jet flew at an average speed of 480 mph from Point X to Point Y. ...
- math - Matt and Anna are frequent fliers on Fast n Go Airplanes. They often fly ...
- MATH - Matt and Anna are frequent fliers on Fast n Go Airplanes. They often fly ...
- math - a private jet flies the same distance in 6 hours that a commercial jet ...
- Math - Elenore made an 850 mile trip east. She traveled 2 hours by jet and 30 ...
- Math - Against the wind, a small palne flew 900 miles in 9 hours. The return ...
- algebra - These are very easy to set up with a "chart" ---------Distance-----...
- math - it took cindy 2h to bike from abbott to benson at a constant speed. the ...
- math - A plane travels 1020 miles from New York City to Minneapolis in 3.3 ...
- physical science - A car travels in a northward direction for a total distance ...

More Related Questions