I have a math problem that i need help with. Its more like a puzzle to solve.
There is a car that travels to a destination averaging 60 mph
It goes back the exact same distance averaging 40 mph
What is the total average speed it travelled...and its not 50 mph
somebody help me
2007-01-03 12:37:22 · 11 answers · asked by monkeyinaplane 2 in Science & Mathematics ➔ Mathematics
1hr @ 60mph
(1hr used for demonstration purposes)
60miles
travelling back at 40mph is 1.5 hours
120 miles in total travelled over 2.5 hours
120/2.5=48mph
2007-01-03 12:52:49 · answer #1 · answered by adriantheace 4 · 0⤊ 0⤋
It travels X distance each way, taking: X mi / 60 mi/hr = X/60 hr going and similarly it takes X/40 hr going back for a total of (X/60 + X/40) hr = 5X/120 hr = X/24 hr * 60 min/hr = 2½ * X minutes. For an average speed, divide that by 2 = 1.25 * X minutes.
The distance doesn't really matter, actually, just the 1.25. (You can see this by setting the distance equal to 1 mi.) Divide 60 mi/hr by the 1.25 and you get 48 mi/hr as the average speed.
2007-01-03 12:49:36 · answer #2 · answered by roynburton 5 · 0⤊ 0⤋
48 mph.
Let's take an example distance of 60 miles. The total travel time would be one hour there and one and a half hours back.
120 miles traveled, 150 minutes to do it...
48 mph.
2007-01-03 12:41:24 · answer #3 · answered by tomgreenfanus 3 · 0⤊ 0⤋
pick a distance any distance, ok 60 miles it takes one hour to get there. 1 1/2 to get back.
120 miles in 2 1/2 hours = 120/2.5
Later you will learn that distance is like area. If the hight represents speed, width represents time area represents distance. Sorry to get of track 48 is the answer.
2007-01-03 13:09:02 · answer #4 · answered by Anonymous · 0⤊ 0⤋
itds 60 miles per hour look
60m=40=20 the 20 being what the 40 id missing from 60 and your answer is 60
2007-01-03 12:40:48 · answer #5 · answered by Anonymous · 0⤊ 1⤋
48 mph
Lets say he went 240 miles. Going 60, it would take him 4 hours. Going 40 it would take him 6 hours. So to go a total of 480 miles it would take him 10 hours.
480/10 = 48
2007-01-03 12:40:03 · answer #6 · answered by aficionado210 2 · 1⤊ 0⤋
Why cant it be 50? 60+40=100 100/2=50! I guess u need more details...
2007-01-03 12:41:57 · answer #7 · answered by Anonymous · 0⤊ 1⤋
First I determine time
T=D/R
(X/60)+(X/40)= (5X/120) = (X/24)Hours
Second I determine distance each way.
D=(T)(R)
D=( X/24)(60) = 2.5X
D=(X/24)(40)= 1.6X
2.5X + 1.6X =4.16X/2= 2.08 Miles (you could round off to '2' )
Last Find the Rate
R = D/T
R = 2.08 / (X/24)
R = 2.08(24X)
R = 49.9 mph
If you rounded Distance above to '2'
R = D/T
R=2(X/24)
R=2(24X)
R=48X
R=48 mph
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2007-01-03 14:55:53 · answer #8 · answered by Anonymous · 0⤊ 0⤋
that is so easy, i ain't gonna tell u the answer cause u know it. u are just thinking too hard about it.
2007-01-03 12:40:18 · answer #9 · answered by whiz 4 · 0⤊ 1⤋
48mph
2007-01-03 12:43:49 · answer #10 · answered by ViVo (: 2 · 0⤊ 0⤋