Question 522686
If a train travels at the speed of 45 km/hr, it is late by 48 minutes.
 If it travels 50 km/hr it arrives exactly on time.
 What is distance the train is traveling (in km)?
:
let d = the distance traveled
then
{{{d/50}}} = the time to arrive on time
and
{{{d/45}}} = the time to be 48 min late
:
Convert 48 min: {{{48/60}}} = .8hrs
:
slower time - ideal time = .8 hrs
{{{d/45}}} - {{{d/50}}} = .8
multiply by 450
450*{{{d/45}}} - 450*{{{d/50}}} = 450(.8)
cancel the denominators, results:
10d - 9d = 360
d = 360 miles is the distance
;
:
:
Check this by finding the times
360/45 = 8.0 hrs, late
360/50 = 7.2 hrs. on time
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differs: .8 hrs which is 48 min