An alarm was set at 11 AM on Monday on a clock that was set correctly at 1 AM on Sunday, but the clockstarted gaining 20 seconds every 24 hours. What was the actual time when the alarm went off?

Correct option is C

Given:

clock gain 20 sec in every 24hrs.

clock was set on right time at 1AM Sunday.

Concept Used:

11hrs = 10:59:60

Solution:

total time difference between 1AM Sunday  and 11AM Monday =

=24hrs(from 1AM Sunday to 1AM Monday ) + 10hrs(1AM to 11AM)

= 34hrs

 clock gain 20 sec in every 24hrs than in 34hrs time gain  = $$\frac{34\times20}{24}$$​        

                                                                                      =28.33 sec

So, actual time =  10:59:60 -0:0:28.33

                        =    10:59:31