Mo2men wrote:
CrackVerbalGMAT wrote:
Hi Chandeep01,
Here is my 2 cents for this question,
Best way to solve this problem is Plugging in for x minutes.
“x” we can take anything, just make sure here we take a multiple of 30 and 20 because its easy for calculation.
Let say x = 120 minutes, that is 2 hours.
Then for two hours Jessica would have travelled,
D = 2 * 30 = 60 kms,
And Nicole would have travelled,
D = 2 * 20 = 40kms,
So Jessica is ahead of Nicole by 20kms and wait for Nicole to join.
So Nicole has to cover 20kms, so it would take an hour for Nicole to cover 20kms.
That’s it, since the answer choices are minutes, one hour = 60 mins.
So we should get the answer as 60 while substituting x = 120.
So the answer is B.
Hope this helps
Dear CrackVerbal,
When I tried the rule that you mentioned in your post below. it did not work properly.
cars-p-and-q-started-simultaneously-from-opposite-ends-of-a-159355.html#p1782046After Nicole passed Jessica, Jessica cycled for certain time the stopped till Jessica cached her up. So it mean that both cycled for same DISTANCE. So I applied the following rule as you mentioned
S1T1 = S2T2...........However It gave me wrong answer D.
Where did I go wrong?
thanks in advance for you help
Hi Mo2men,
You have done the first part right in identifying that the distance traveled by both Nicole and Jessica is a constant.
Let SN and TN be the speed and time of Nicole and SJ and TJ be the speed and time of Jessica.
Since the distance is constant
SN*TN = SJ * TJNow the time taken by Jessica after she passes Nicole is 'x' minutes. After travelling for 'x' minutes Jessica stops and waits for Nicole.
So the total time taken by Jessica to travel the constant distance is 'x' minutes.Jessica travels for the initial 'x' minutes and an additional 'y' minutes when Nicole is at rest (waiting for her to catch up).
So the total time taken by Jessica to travel the constant distance is 'x + y' minutes. Here we need to find the value of y with respect to x
So substituting the speeds and times in
SN*TN = SJ * TJ we get
20(x + y)/60 = 30(x)/60 ; Dividing by 60 since the time is in minutes
Simplifying we get x = 2y -----> y = x/2
Answer : B
Hope this helps!
CrackVerbal Academics Team
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www.crackverbal.com