EgmatQuantExpert wrote:
Q.)
James started from his home and drove eastwards at a constant speed. Exactly 90 minutes after James stated from his home, his brother Patrick started from the same point and drove in the same direction as James did at a different constant speed. Patrick overtook James exactly 90 minutes after Patrick started his journey and then continued driving at the same speed for another 2 hours. By what percentage should Patrick reduce his speed so that James could catch up with Patrick in exactly 8 hours after Patrick overtook James?
A. 25%
B. 33%
C. 50%
D. 67%
E. 75%
Thanks,
Saquib
Quant Expert
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Hi
Since the distance covered by James in (90+90) minutes is same as Patrick in 90 minutes, speed of P is TWICE that of J..
Now it will be easier to give a number to each..
Let J's speed be 1kph, so P's speed will be 2kph....
We are looking for both to meet after 2+8 hour..
So in 10 HR , J will travel at constant rate @1kph= 10*1=10km..
P travels at 2kph for 2 hrs so travels 4km...
Remaining Kms=10-4=6...
So Phase to travel 6km in remaining 10hr...
So speed becomes 6/8=3/4 kph...
Reduction=2-3/4=5/4
%=(5/4)/2*100=5/8 *100=500/8=62.5%
EgmatQuantExpert pl correct your choices as you are asking for "meeting in EXACT 8 hrs"..
I agree they are meeting in exactly 8 hours, but then the last line clearly states - "in exactly 8 hours
In the given solution presented here, you have considered 8+2 hours, which is incorrect.
The percentages have been rounded off in the options. But then if you find the correct solution, it will be easy to figure out the correct option.
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