At noon a private plane left Austin for Los Angeles, 2100 km away, flying at 500km/h. One hour later a jet left Los Angeles for Austin at 700 km/h. At what time did they pass each other
please show work...
2007-11-01 16:33:14 · 9 answers · asked by littlepeculiar13 2 in Science & Mathematics ➔ Mathematics
I wouldn't ask if I didn't need "help badly". If you can't, go away
2007-11-01 16:39:22 · update #1
thank you so much Ron. you get 10 points. although I think you had it right the first time 2800/1200 = 2.333333.
2007-11-01 17:08:30 · update #2
Read the problem for each piece of information you need. Start with the answer, what time, not how long.
The total distance is 2100, the units are km.
You can think of this as two rates, one rate for the first hr and a second rate for both planes flying toward each other.
One plane has a head start, lets find out how far it goes before the second plane starts.
500k head start. The second rate is the sum of the two rates because they are flying at each other. 1200 km/hr.
The remaining distance is 2100 - 500, 1600 km.
We need to solve for time, we have distance.
d=rt ; solve this for time (how long)
d/r=t ;divide both sides by r,
1600/1200 = 1.33hrs
We add the solo flight time and it is 2.33 hrs
Convert .33 hrs to minutes we multiply 0.33 x 60 = 20
So 2 hrs and 20 minutes after 12:00 noon, the answer is 2:20PM
2007-11-01 16:48:44 · answer #1 · answered by Ron H 6 · 1⤊ 0⤋
We know the total distance is 2100. One plane will fly a distance of X and the other a distance of 2100-X
Using D=RT
Plane one is X = 500( t +1)
Plane two is 2100-X = 700 t
Plane one X=500t + 500
Plane two 2100 - X = 700t
Add the two equations
2100 = 1200 t + 500
12t = 16
t = 1 1/3 hours
So they pass each other at 1 hour and 20 minutes after the Los Angeles jet leaves and 2 hours and 20 minutes after the private plane leaves..
2007-11-01 16:35:27 · answer #2 · answered by ignoramus 7 · 0⤊ 2⤋
ok plz do not blame me if i'm wrong im just a geeky 8th grader trying to study while on vay-k
: : Work:
2100km=500(t) : 2100 divided by 500 = 4.2
:
2100km=700(t) : 700 divided by 2100 = 3.
:
: 12:00 to 4:02 = Austin to LA
: 12:00 to 3:00 = La to Austin
My Guess is the answer is 3: 51 plz don't blame me 4 the wrong answer ur the ones thts cheating in the 1st place...
2007-11-01 16:57:42 · answer #3 · answered by Anonymous · 0⤊ 0⤋
think that she travelled for x hours at 60 mph, so she might have travelled for (6 - x) hours at 20 mph, so: 60x + 20(6 - x) = 240, so 60x + a hundred and twenty - 20x = 240, so 40x = a hundred and twenty, so x = a hundred and twenty/40, so x = 3. So, she travelled for 3 hours at 60 mph, and 3 hours at 20 mph. She travelled a hundred and eighty miles at 60 mph, and 60 miles at 20 mph. verify a hundred and eighty + 60 = 240, so the answer is right.
2016-12-30 14:00:34 · answer #4 · answered by ? 4 · 0⤊ 0⤋
Alright, you know what... you can't worry about all this Newtonian kinematics... it won't help you be good in life, it's boring... All you need to do is lift weights greatly, get a hot BMW 7-Series, and play football for the University of Texas, but you must be good, pretty darn good, okay? Don't waste your best years on this boring kinematic equation crap. Be a Colt McCoy, please?
2007-11-01 16:39:56 · answer #5 · answered by Anonymous · 1⤊ 0⤋
distance = rate multiplied by time ...the answer is probably in the back of your textbook since youre cheating.
2007-11-01 16:39:22 · answer #6 · answered by sk939 2 · 0⤊ 0⤋
multiply the rate at which traveled by the time the person was traveling. u will find the answer
2007-11-01 16:36:48 · answer #7 · answered by Anonymous · 0⤊ 0⤋
I agree. You should do your own homework, unless you majorly need help badly.
2007-11-01 16:37:07 · answer #8 · answered by Miss Princess! 2 · 0⤊ 1⤋
do your own homework. you will never graduate by asking questions on yahoo answers
2007-11-01 16:35:57 · answer #9 · answered by jessica_6902 2 · 0⤊ 2⤋