It is currently 9:40 AM. What will be the time in next 610 hours?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 7:40 PM
Every 24 hours the clock shows the same time again, so only the remainder on division by 24 matters:
\(610 = 24 \times 25 + 10\)
\(610 \equiv 10 \pmod{24}\)
So the time after 610 hours is the same as after 10 hours:
9:40 AM + 10 hours = 7:40 PM
Why the other options are incorrect
Option (1) 9:50 AM — Incorrect. This adds 10 minutes; the remainder 10 is in hours.
Option (2) 7:40 AM — Incorrect. 10 hours after 9:40 AM passes noon, so the time is in the evening (PM).
Option (3) 9:50 PM — Incorrect. 9:50 PM is 12 hours 10 minutes after 9:40 AM, not 10 hours.
CBSE Applied Mathematics (Class XII):
Application of Modulo Arithmetic
