Question

A wrist watch which is running 12 minutes late on a Sunday noon is 16 minutes ahead of the correct time at 12 noon on the next Sunday. When is the clock 8 minutes ahead of time?

• A. Thursday 10 am
• B. Friday noon
• C. Friday 8 pm
• D. Tuesday noon

Answer 1

The correct option is B Friday noon

Given : On a Sunday noon, The wrist watch is running 12 minutes late i.e Actual time - 12 minutes.

On the next Sunday, the wrist watch is running 16 minutes ahead i.e Actual time + 16 minutes.

So, the watch has been pacing up during the week and has made a difference of (Actual time + 16 minutes) - (Actual time - 12 minutes) = 28 minutes, across the week.

Hence, in one day it gains no. of minutes = (28 minutes)/(7 Days) = 4 minutes/Day.

Now, to make the clock run 8 minutes ahead i.e Actual time + 8 minutes, the difference it should make = (Actual time + 8 minutes) - (Actual time - 12 minutes) = 20 minutes.

To make up this difference of 20 minutes, it would take = (20 minutes)/(4 minutes/Day) = 5 Days.

So, from Sunday noon, it would take exactly 5 days to get the clock run 8 minutes ahead of time.

Hence, Sunday noon + 5 days = Friday noon.

Thus, the correct option is B Friday noon.