Mr. Hill drives to toronto. One fay his average speed going to work was 80km/h but returning it was only 70km/h. If his total travelling time that day was 3 hours, how far from toronto is his home?
2006-12-30 10:59:23 · 5 answers · asked by Cutie 4 in Science & Mathematics ➔ Mathematics
Let x be the time it drives to work, then the time to drive home is
3-x.
The distance is the same to work and back from work so
80x = 70(3-x)
80x = 210-70x
150x=210
x=1.4
The distance is 80x= 80*(1.4)= 112km
2006-12-30 12:30:34 · answer #1 · answered by CAM1122 3 · 1⤊ 0⤋
80 x = time to travel to work
70 x = time to return
80x + 70x = 3 hours
150 x = 3 hours (180 min)
x = 180/150 = 1.2 min
80 x 1.2 = 96 k
70 x 1.2 = 94 k
total = 180 k
this is return trip mileage
therefore divide 180 by 2 = 90 k from toronto
2006-12-31 00:21:35 · answer #2 · answered by David C 2 · 0⤊ 0⤋
Let t be driving time to toronto, then 3-t is the returning time.
Balance by the one-way distance d:
80t = 70(3-t) = d
t = 1.4 hr
d = 80t = 112 km
2006-12-30 20:48:26 · answer #3 · answered by sahsjing 7 · 0⤊ 0⤋
adv. speed 75 x 3hr= 225
2006-12-30 20:25:21 · answer #4 · answered by Captgoody 2 · 0⤊ 1⤋
omg that is diff sorry cant help
2006-12-30 19:01:40 · answer #5 · answered by Princess Cheerleader 1 · 0⤊ 1⤋