Split the number into hundreds, tens and ones and then add hundreds, tens and ones separately.

Add tens and ones separately.

Think the closest number of 487 and 456.

Add 1400 to 7890, then take away 1 ones.

First add ones to the number and then tens.

Add hundreds, tens and ones seperately.

Add tens and ones separately.

First find how many boys and girls left there to watch the match.

First find how many boys and girls left there to watch the match.

Identify the keywords and think, which operation do we need to use.