Question

A man starts his journey from Bangalore to Delhi by train. He starts at 23.30 on Wednesday. If it takes 34 hours of travel time to reach Delhi and if the train is not late, when will he reach Delhi?

• A. Friday at 6.30 hours
• B. Friday at 9.30 hours
• C. Saturday at 6.30 hours
• D. Saturday at 9.30 hours

Answer 1

The correct option is B Friday at 9.30 hours

Given starting time is 23.30.
Travel time is 34 hours.
The reaching time = start time + travel time
Here, we use modulo 24 as one day has 24 hours.
$\Rightarrow (23.30+34)\left(mod24\right)\equiv 57.30\left(mod24\right)$
$\equiv 9.30\left(mod24\right)$
Hence, the man would reach at 9.30 hours.
To find the day that he reaches:
The man travels for 34 hours and we know that a day has 24 hours.
$\Rightarrow 34=1\times 24+10$
$\Rightarrow$He travels for 1 day (Thursday) and 10 hours (on Friday).
$\therefore$ Starting the journey on Wednesday, he would reach Delhi on Friday at 9.30 hours.