James and Tom run around a track of 4200 m. They start together. James runs at a speed at 140m/minute. Tom runs at 100m/s. James rests 1 minute when he goes back to the start. Tom rests 3 minutes when he goes back to the start. When do they meet again?
And how do I do questions like this?

Question

James and Tom run around a track of 4200 m. They start together. James runs at a speed at 140m/minute. Tom runs at 100m/s. James rests 1 minute when he goes back to the start. Tom rests 3 minutes when he goes back to the start. When do they meet again?
And how do I do questions like this?

king · Answer

they ran around a track of 4200 m what?radius ,circumference,area?

lollylau · Answer

circumference

king · Answer

they rest for a certain time and start again rite?

lollylau · Answer

yep

king · Answer

first convert 140m/min to m/s
=140*1/60=7/3

lollylau · Answer

tom's speed is 100/min, but never mind

king · Answer

what !!tom;s speed is 100m/min or s?

lollylau · Answer

MINUTE! =.=

king · Answer

ok so find time taken for both to complete one round of the circle
james=4200/140=30 minutes
tom=4200/100=42 minutes

lollylau · Answer

ok

king · Answer

so if they meet after x rounds of the circle the time taken by each of them will be 30x and 42x

lollylau · Answer

but then they rest rite?

king · Answer

oh yeah sry it will be 31x and 45x[30x+x,42x+3x]

lollylau · Answer

then...

phi · Answer

The easiest way to do this is find the average speed, S= D/T  where T includes the rest time.
Then find S1*T mod 1400 = S2*T mod 1400  (this assumes they meet somewhere on the track.

Then, to be sure, check that they do not meet at the start while one or the other is resting before they meet on the track.