Discussion of Question with ID = 059 under Clocks-and-Calendars

This is the discussion forum for this question. If you find any mistakes in the solution, or if you have a better solution, then this is the right place to discuss. A healthy discussion helps all of us, so you are requested to be polite and soft, even if you disagree with the views of others. The question and its current solution has also been given on this page.

Advertisement

Question

Two watches, one of which gained at the rate of 1 min. and other lost at the rate of 1 min. daily, were set correctly at noon on the 1st January 1977. When did the watches indicate the same time?

A

Dec. 27, 1977 midnight

B

Dec. 26, 1977 noon

C

Dec. 25, 1977 noon

D

Dec, 27, 1977 noon

Soln.
Ans: d

The first watch gains on the second watch 1 + 1, 2 minutes in a day.
The watches will indicate the same time when the one has gained 12 hours on the other. As 2 minutes is gained in 1 day
∴ 12 hours is gained in days = 1⁄2 x 12 x 60 = 360 days
Counting 360 days from 1st Jan. 1977, we get Dec. 27, 1977.

Comments and Discussion