Mr. Mike took a two-day automobile trip. What was her average speed in

Question

Mr. Mike took a two-day automobile trip. What was her average speed in kilometers per hour while driving?

(1) She drove 300 killmeters the first day and 267 killometers the second day.
(2) She drove exactly one hour longer the first day than she did the second day.

yashikaaggarwal · Answer

Average speed =  \frac{Total distance}{Total time taken}

(1) She drove 300 killmeters the first day and 267 killometers the second day.
Neither Speed nor time is given (insufficient)

(2) She drove exactly one hour longer the first day than she did the second day.
Distance is not given..
(Insufficient)

Combining both:  \frac{Total Distance}{Total time taken}  = Average Speed.
 567/  \frac{300}{t} + \frac{267}{t+1} = Average speed.

567/  \frac{(300t + 300)+267t}{t^2+t}  = Average speed.

\frac{567t^2+567t}{567t+300}

We have no further equation of constraint to solve for t.
(Insufficient)

Answer is E

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Archit3110 · Answer

target find total distance / total time = avg speed
#1
She drove 300 killmeters the first day and 267 killometers the second day.
speed of both days not know insufficient
#2
She drove exactly one hour longer the first day than she did the second day.
day 2 be x hrs
time day 1; x +1 hrs
insufficient as distance is not know
from 1 &2
we get
300/x+1 + 267/x
but value of x is not know insufficiet
OPTION E ;

Nipungupta9081 · Answer

IMO E

Average speed = Total Distance/ Total time take

Statement 1 - only speed is given that is 300 and 267
Neither distance or time is given - NOT SUFFICIENT.

Statement 2 - She drove exactly one hour longer the first day than she did the second day

Only time is given --- NOT SUFFICIENT.

Combining Both = 300 / x +1 + 267 / x

We can't find the value of X

NOT SUFFICIENT

Posted from my mobile device

VERBAL1 · Answer

yashika   Bunuel   Archit3110  and other senior moderators, this is the approach that I used please tell me why is it incorrect:

Calculating the rate for the first day:
t+1=300/r
 
Calculating the rate for the first day:
t= 267/r

Can't t be substituted in the first equation to derive 
267/r + 1=300/r

Please let me know.
TIA

Hama95 · Answer

isn't a day in the question enough to assmue she drove for 12 h ? without stoping

RohitSaluja · Answer

By combining both the equation should be 567/2t + 1, as we know t was the time taken during first leg of the trip and t+1 during second leg. I am not sure why have you put 300/x and 267/x+1

Mr. Mike took a two-day automobile trip. What was her average speed in

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Mr. Mike took a two-day automobile trip. What was her average speed in

Prep Toolkit

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My Rewards