Start taking away from the ones place first.

Start taking away from the ones place first.

Use inverse operation and take away.

Take away 1000 from 1100 and then add one.

Start taking away from the ones place first.

Start taking away from the ones place first.

Take away 1000 from 1100 and then add one.

Use inverse operation and take away 8988 from 9876.

Think how much can we add to 7999 to get 8000.