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some questions of TSD
by Nakul Kothari - Thursday, 17 February 2011, 12:36 PM
  Hey guys do help me out in these questions:-

Q. Mrinalini and NEha travel to Cannaught Place along two straight roads with constant speeds. At the initial moment the positions of Mrinalni, Neha and Canaught Place form a right triangle. After Mrinalini travelled 30 km, the triangle between the points became equilateral. Find the distance between Mrinalini and Neha at the initial moment if at the time Mrinalini arrived at Connaught Place, Neha had to cover 66.66 km to reach Cannaught Place?

b) 30(5)1/2
c) 12(3)1/2
e)None of these

Q.2.  A motorist leaves the post office to go to the airport to collect mail. The plane arrives early and the mail is sent on a horse cart . After half an hour the motorist meets the horse cart collects the mail and returns to the post office, thus saving 20 minutes. how many minutes early did the plane arrive?
a) 20

Re: some questions of TSD
by TG Team - Friday, 18 February 2011, 03:39 PM

Hi Nakul smile

I feel there is some language/data problem with both the questions.

1) It can be easily inferred that right triangle under consideration is 30-60-90 triangle, so all the sides lengths can be found in one variable only and then we can easily compare the ratio of speeds of Mrinalini and Neha to get the variable part.

2) Again there is bit confusion in language. Half an hour mentioned is the time taken by the horse-cart and not motorist. After this , I believe, problem becomes a cake-walk. Answer is simply = 30 + (20/2) = 40 minutes. smile

Kamal Lohia   

Re: some questions of TSD
by manu mehta - Tuesday, 14 April 2015, 12:46 AM
  I think the answer should be 20.
The horse cart took 30 min for the travel for which the motorist should have taken 10 min. So effectively, 30 - 10 = 20 mins have been saved and correspondingly the plane arrived 20 mins earlier. Isn't it?