A clock gains 3 minutes every hour. It is set correctly at 6:00 am on Monday. What time does it show at 6:00 pm on Tuesday of the same week?
Answer and explanation
Correct answer: C. 7:48 pm
- Step 1: From 6:00 am Monday to 6:00 pm Tuesday is 36 hours. Step 2. The clock gains 36 × 3 = 108 minutes, which is 1 hour 48 minutes. Step 3. 6:00 pm + 1 hour 48 minutes = 7:48 pm. Answer: 7:48 pm. Why not the others: 6:36 pm: This counts only 12 hours of gaining, 12 × 3 = 36 minutes, instead of the full 36 hours. 7:08 pm: This writes 108 minutes as 1 hour 8 minutes instead of 1 hour 48 minutes. 4:12 pm: This subtracts the 108 minutes, as if the clock were losing time.
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