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1. Wall clock gains 2 minutes in 12 hours, while a table clock loses 2 minutes every 36 hours. Both are set right at 12 noon on Tuesday. The correct time when both show the same time next would be = ?
After 12 days, i.e., after 12 × 24 hours clock B will loose 16 minutes and will show 11 : 44 am
The two clocks will show the same time after time after 135 days.
The time difference has to be 12 hours between then = 720 minutes.
A will gain 540 minutes in 135 days.
B will loose 180 minutes in 135 days, total 720 minutes.
Further if we consider only time then the problem becomes simpler
Total difference of minutes between the times shown by the clocks after 36 hours
⇒ minutes difference in 1 day
⇒ 12 × 60 minutes difference in × 12 × 60 = 135 days
∴ 12 noon, after 135 days
Solution:
After 12 days, i.e., after 12 × 24 hours clock A will gain 48 minutes and will show 12 : 48 noon.After 12 days, i.e., after 12 × 24 hours clock B will loose 16 minutes and will show 11 : 44 am
The two clocks will show the same time after time after 135 days.
The time difference has to be 12 hours between then = 720 minutes.
A will gain 540 minutes in 135 days.
B will loose 180 minutes in 135 days, total 720 minutes.
Further if we consider only time then the problem becomes simpler
Total difference of minutes between the times shown by the clocks after 36 hours
⇒ minutes difference in 1 day
⇒ 12 × 60 minutes difference in × 12 × 60 = 135 days
∴ 12 noon, after 135 days