Quantitative Aptitude - Arithmetic Ability Questions

The watch gains 5 seconds in 3 minutes = 100 seconds in 1 hour.

From 8 AM to 10 PM on the same day, time passed is 14 hours.

In 14 hours, the watch would have gained 1400 seconds or 23 minutes 20 seconds.

So, when the correct time is 10 PM, the watch would show 10 : 23 : 20 PM

                                                A    :    B    :    C   

Ratio of efficiency               3     :    1    :    2   

Ratio of No.of days            1/3  :   1/1  :   1/2    

     or                                       2    :    6    :    3   

Hence A is correct.  

Time taken by one tap to fill half of the tank = 3 hrs.

  Part filled by the four taps in 1 hour =4*1/6 =2/3

Remaining part =1-12=12

23:12::1:x

=> x = 12*1*32=34

So, total time taken = 3 hrs. 45 mins.

Time from 7 am to 4.15 pm  = 9 hrs 15 min = 374 hrs 

3 min. 5 sec. of this clock = 3 min. of the correct clock. 

Now 3min.5sec. is37720 hrs of this clock = 3 min.is120 hrs of the correct clock 

374 hrs of clock = 120×72037×374 hrs of the correct clock. 

  = 9 hrs of the correct clock. 

 The correct time is 9 hrs after 7 am. i.e., 4 pm.