2006-08-05 18:02:18 · 4 answers · asked by Ervsha 1 in Science & Mathematics ➔ Mathematics
<-------60km------->
A--------------|-------V
p = the meeting point (the place with the vertical line)
let distance betweenV and p be "x"
then distance between A and p is "60-x"
let the time elapsed be "t"
time = distance/speed
ie for A t=60-x/4 (eqn 1)
and for V t=x/3 (eqn 2)
ie 60-x/4 = x/3
ie 180-3x=4x
ie 7x=180
ie x=180/7
put x in (eqn 1) or (eqn 2) [I put in (eqn 2) 'cause its easier to solve]
therefore t=60/7 hrs
A and V will meet after 60/7 hrs or 8.57 hrs or 8hrs 34mins
2006-08-05 20:48:10 · answer #1 · answered by Anonymous · 0⤊ 0⤋
T is elapsed time.
3 km/hr * T hr + 4 km/hr * T hr = 60 km
7 T = 60
T = 60/7 = 8 4/7 hr.
But 4/7 hr = (4 * 60)/7 = 34 1/2 min.
They'll meet in 8 hrs, 34 1/2 min.
2006-08-06 01:27:43 · answer #2 · answered by bpiguy 7 · 0⤊ 0⤋
they will be talking towards each other at a rate of 7 km an hour.. therefore they will be 6 km apart after 6 hours (7*6=54, 60-54=6) plus the additional time for them to close the gap for the remaining 6 km since V will walk only 3/7 of the way of the 6 km to meet A who wil travel 4/7 of the way... so 3/7 of 6 km is 18/7 km*(1 hr/3km) for 6/7 of an hour so they will meet in 6 and 6/7 hours
2006-08-06 01:16:50 · answer #3 · answered by escotia21 2 · 0⤊ 0⤋
8 2/5 HOURS
2006-08-06 01:27:53 · answer #4 · answered by MIGHTY MINNIE 6 · 0⤊ 0⤋