Two airplanes are 300 miles apart flying directly toward each other. One is flying at 200 miles per hr and the other at 160 miles per hr. how long will it take for the two to meet?
An easy strategy to follow for this kind of question will be much appreciated. Cheers!
a. 36 mins
b. 50 mins
c. 1 hr 12 mins
d. 1 hr 40 mins
e. 1 hr 41 mins
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pemdas
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the distance between two airplanes is D, D=300
two airplanes fly directly toward each other means their combined distances will be equal to D or 300
we need to find time when two airplanes meet - only one time, momentum, hence t(1)=t(2) or simply T
D(1)+D(2)=D and 200*T + 160*T = D since time is one value for both airplanes
360*T=300, T=300/360, T=5/6 hour or 50 minutes
b
two airplanes fly directly toward each other means their combined distances will be equal to D or 300
we need to find time when two airplanes meet - only one time, momentum, hence t(1)=t(2) or simply T
D(1)+D(2)=D and 200*T + 160*T = D since time is one value for both airplanes
360*T=300, T=300/360, T=5/6 hour or 50 minutes
b
Vishnu88 wrote:Two airplanes are 300 miles apart flying directly toward each other. One is flying at 200 miles per hr and the other at 160 miles per hr. how long will it take for the two to meet?
An easy strategy to follow for this kind of question will be much appreciated. Cheers!
a. 36 mins
b. 50 mins
c. 1 hr 12 mins
d. 1 hr 40 mins
e. 1 hr 41 mins
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Tani
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You can also eyeball this one. In one hour the two planes will have traveled 360 miles - too far, so that leaves out C,D, and E.
Looking at the other two answers, your 360 is pretty close to 300, so the answer will be fairly close to one hour - 50 minutes works.
Looking at the other two answers, your 360 is pretty close to 300, so the answer will be fairly close to one hour - 50 minutes works.
Tani Wolff
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GMATGuruNY
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When elements work together to complete a task or to travel a distance, we can add their rates.Vishnu88 wrote:Two airplanes are 300 miles apart flying directly toward each other. One is flying at 200 miles per hr and the other at 160 miles per hr. how long will it take for the two to meet?
An easy strategy to follow for this kind of question will be much appreciated. Cheers!
a. 36 mins
b. 50 mins
c. 1 hr 12 mins
d. 1 hr 40 mins
e. 1 hr 41 mins
Since the two planes are traveling toward each other, they are working together to travel the distance of 300 miles.
Their combined rate = 200+160 = 360 miles per hour.
Time = d/r = 300/360 = 5/6 hours = 50 minutes.
The correct answer is B.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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