Question

An exam starts at 11.45 am and lasts for 45 minutes. At what time does the exam finish?

• A. 12:30 pm
• B. 1:30 pm
• C. 2:30 am
• D. 12:15 pm

Answer 1

The correct option is A

12:30 pm

In 11:45, 45 represents minutes.
So we can write, 11:45 = 11 hours 45 minutes.
Now from this time we need to add 45 min, we just add and we get 90 minutes.
90 minutes can be written as (60 + 30) min.
Finally, we can write,
11.45 + 0.45 = 11 hours 90 minutes
= 11 hours + 60 minutes + 30 minutes
= (11 + 1) hours + 30 minutes
[ $\because$ 60 minutes = 1 hour]

i.e. (11 + 1) hours + 30 minutes
= 12 hours 30 minutes or 12:30 pm.
[pm is used to describe the second portion of the day, starting from noon right after 12 to just before 12 midnight.]

Hence, the exam finishes at 12:30 pm.