Question

If a clock gets slow by 5 minutes every hour, and it was correct at 6 AM on Monday, what will be the time at 6 PM on Tuesday?

Hint:

For slow or fast clock problems, always compare shown time with actual time using ratios.

Answer 1

Step 1: Calculate the total actual time passed.
From Monday 6 AM to Tuesday 6 PM, the total time elapsed is:
\[ 24 + 12 = 36 \text{ hours} \]
Step 2: Determine the speed of the clock.
The clock loses 5 minutes every hour, so in 60 minutes it shows only 55 minutes.
Thus, the clock runs at \( \frac{55}{60} \) of real time.
Step 3: Find the time shown by the clock.
Time shown by the clock in 36 hours:
\[ 36 \times \frac{55}{60} = 33 \text{ hours} \]
Step 4: Calculate the final time.
Starting from 6 AM Monday, adding 33 hours gives:
\[ 6 \text{ AM} + 33 \text{ hours} = 3 \text{ PM (Tuesday)} \]
Step 5: Conclusion.
The clock will show 3 PM.