Multiple choice

A clock is 5 minutes slow at 4:35 p.m. on Monday and 12 minutes fast at 5:45 a.m. the following Monday. If the clock gains uniformly, then when did it show the correct time?

  1. 1:46:30 p.m. on Wednesday

  2. 2:48:30 p.m. on Wednesday

  3. 2:53:23 p.m. on Wednesday

  4. 2:45:00 a.m. on Thursday

  5. 2:45:00 a.m. on Tuesday
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The total time from Monday 4:35 p.m. to the following Monday 5:45 a.m. is 7 days and 1 hour and 10 minutes, which is 169 hours and 10 minutes (10150 minutes). The clock gains 5 + 12 = 17 minutes in this interval. To show the correct time, it must gain the 5 minutes it was slow. Time taken = (5/17) * 10150 minutes = 2985.29 minutes, which is 49 hours and 45 minutes. Adding this to Monday 4:35 p.m. results in Wednesday 2:20 p.m. plus adjustment for the 17 minutes gain rate.

Keep practicing — related questions