If today is Friday, then what will be the day after 129 days?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Monday
Days repeat every 7 days, so only the remainder on division by 7 matters:
\( 129=7\times 18+3 \)
\( 129\equiv 3\pmod 7 \)
Three days after Friday: Saturday, Sunday, Monday.
CBSE Applied Mathematics (Class XII):
Modulo Arithmetic
