If it is 7:00 pm currently in the clock, what will the clock show (in am or pm) after 674 hours?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 9:00 pm
The clock shows the same time every 24 hours, so only the remainder on division by 24 matters:
\(674 = 24 \times 28 + 2\)
\(674 \equiv 2 \pmod{24}\)
After 28 full days the clock again shows 7:00 pm, and 2 more hours take it to 9:00 pm.
CBSE Applied Mathematics (Class XII):
Congruence Modulo
