Question

I have doubts in subtraction on time.eg subtract 3hr46min27sec from 6hr 35 min 15 sec. How to calculate this?

Answer 1

Follow these steps:

• Subtract the hours
• Subtract the minutes
• If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Like this:

Easy example: What is 4:10 - 1:05 ?

Subtract the Hours: 4−1 = 3
Subtract the Minutes: 10−5 = 5

The minutes are OK, so the answer is 3:05

Hard example: What is 4:10 - 1:35 ?

Subtract the Hours: 4−1 = 3
Subtract the Minutes: 10−35 = −25

The minutes are less than 0, so:

• add 60 to Minutes (−25+60 = 60−25 = 35Minutes)
• and subtract 1 from Hours (3−1 = 2Hours)

The answer is 2:35

(Note: did you see how we changed "−25+60" to "60−25" ... that is perfectly fine and makes the calculation easier.)

I hope u understand
Cheers!!