Q1:jipmat 2025LRDI › Clocks & CalendarsMediumLR · MCQ

A watch is 1 minute slow at 1 p.m. on Tuesday and 2 minutes fast at 1 p.m. on Thursday. When did it show the correct time?

• A1:00 am on Thursday
• B5:00 pm on Wednesday
• C1:00 pm on Wednesday
• D5:00 am on Wednesday

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The Setup: We need to calculate the total time elapsed and the total time gained by the faulty watch to figure out exactly when it crossed the threshold of the correct time. Step 1: Calculate the total time and total gain * From Tuesday 1 p.m. to Thursday 1 p.m. is exactly 48 hours. * The watch goes from being 1 minute slow ($-1$) to 2 minutes fast ($+2$). * Total time gained = $1 + 2 = 3$ minutes. So, the watch gains 3 minutes every 48 hours. Step 2: Dox the correction point Since the watch started exactly 1 minute slow, it needs to gain exactly 1 minute to show the correct time. * If it gains 3 minutes in 48 hours... * It gains 1 minute in $\frac{48}{3} = 16$ hours. Step 3: Secure the target time We just add 16 hours to the starting time (Tuesday 1 p.m.). * Tuesday 1 p.m. + 12 hours = Wednesday 1 a.m. * Wednesday 1 a.m. + 4 hours = Wednesday 5 a.m. Final Answer: 5:00 am on Wednesday