Two cars A and B having average speeds of 40 and 50 MPH, respectively, are 360 miles apart. They start moving toward each other at 2:00 pm, at what time will they meet? Can you give me an answer and show how you got it? Thanks a lot! It would really help.
2007-01-03 20:16:37 · 12 answers · asked by tinywee 2 in Science & Mathematics ➔ Mathematics
1. Find their relative speed. Since they are moving towards each other, the relative speed is 40 +50 = 90mph.
2. Find the time to cover the given distance, using the relative speed. t = distance / speed = 360 / 90 = 4 hrs.
3. Find the time they would meet = 2:00pm + 4 hrs = 06:00 pm.
2007-01-03 20:45:47 · answer #1 · answered by apollo 2 · 1⤊ 0⤋
mph stand for miles per hour so if you took the mph of each driver A and B and added it together 40+50=90 and 360 devided by 90 is 4 so take 2:00 and add 4 hours to 6:00 and 6:00 is your answer
2007-01-03 20:21:54 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Do not thumbs down until you have read the entire answer. Speed limits, although legal, are actually only there to indicate to people the maximum safe speed for that particular stretch of road. For example, on an A class road where visibility is perfect with no hidden problems and the weather is dry it may be perfectly safe to do 60mph. The next day it may be snowing with patches of ice on the same road therefore it would be unsafe to do even 30mph. Now reduce the speed limit to 40mph and it may be safe one day to do this speed but on the next it may not. A good experienced driver does not need to be told what is a safe speed, they should know without a sign telling them. However an inexperienced driver may think because the sign says 60 or 50 or 40 it must be safe to do that. Again, however, an experienced driver does not automatically mean a good driver and will maybe decide to do whatever speed they want and to hell with the consequences. Without giving another 100 examples do you see that just changing speed limits is not the answer. If the government was serious about reducing road accidents there are numerous things they could do but because it would cost them votes they will never do it. Some examples are 1. Automatic retesting of anyone held responsible for an accident. 2. Automatic retesting for everyone every 10 years. 3. Stiffer penalties for repeat offenders. 4. Automatic disqualification for life if you are held responsible for 3 accidents. Now I know most drivers would never accept those examples which is why I say no government will ever introduce them but it is something like those which are needed if we are ever going to seriously cut down on needless death on our roads. Driver attitude is the key and so long as we have drivers who couldn't care less we will continue to have unnecessary accidents and deaths on our roads.
2016-03-29 07:03:52 · answer #3 · answered by Anonymous · 0⤊ 0⤋
since the cars are moving towards each other their relative speeds will add up
that is in 1 hour they would have moved 40+50=90 miles towards each other
the time taken to meet will be the distance/relative speed
=360 miles/90 mph
=4 hours
so they will meet at 6.00 p.m.
2007-01-03 21:03:51 · answer #4 · answered by raj 7 · 0⤊ 0⤋
!___40___80___120___160
200___150___100___50___!
The diagram shows the car on the left driving for 4 hours at 30mph
and car on the right driving for 4 hours at 50 mph.
That is the point at which they meet - 4 hours
add 4 hours to 2 pm and you will get 6 pm
The distance is 360 miles and the combined speed is 90 mph
divide 360 by 90 and you will get 4 hours
2007-01-04 01:26:57 · answer #5 · answered by David C 2 · 0⤊ 0⤋
Let's say A starts at 0, and B starts at 360 along an axis.
After t hours, A will be at position 40t and B will be at position 360 - 50t. So equate these to find out how many hours elapse before A and B are at the same point. Add this number of hours to 2:00pm et voila!
2007-01-03 20:19:26 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Average speed is got by: time taken divide by speed taken
so 40 divide by 60 (hr) times 360 then 50 divide by 60 times 360 after add the result then i.e 540 divide by 360 your answer will be 1.5hour equivalent to 2hours. they will meet at 4.00 pm
2007-01-03 20:34:25 · answer #7 · answered by ConRob 2 · 0⤊ 0⤋
6 PM.The trip will take them four hours. I am not sure of the equation to solve this problem, but if you take the total distance, it should be divided by the total mph of both cars combined.
360 divided by (40+50)
or
360 divided by 90 = 4
hope this helps
2007-01-03 20:23:58 · answer #8 · answered by Lo 2 · 0⤊ 0⤋
Just to finish what Renny started...
40t = 360 - 50t (add 50t to both sides)
90t = 360 (divide both sides by 90)
t = 4
They will meet 6pm.
2007-01-03 20:24:54 · answer #9 · answered by gebobs 6 · 0⤊ 0⤋
6 PM
Closing speed is 90MPH
90PH into 360Miles is 4
Add 4 hrs to 2pm you have your answer.
Unless of course the car is RED!. That changes every thing things would speed up
2007-01-03 20:21:54 · answer #10 · answered by The Guru 2 · 0⤊ 0⤋