answersLogoWhite

0

When you subtract (for example) 31 - 15, you have to "borrow" from the ten's place, converting 31 (which is 3 tens and 1 unit) to 2 tens and 11 units.

Similarly, when subtracting times, you convert (in this case) the 3 hours to 2 hours and 60 minutes (you convert one of the hours to the equivalent of 60 minutes). Now you can subtract hours minus hours, and minutes minus minutes.

User Avatar

Wiki User

14y ago

What else can I help you with?