Choose the most efficient strategy

~10 min

Some problems are easier with mental math, some with place value, and some with a written method.

Tens and ones

47
4 tens
7 ones

A 2-digit number has tens and ones. The tens digit tells how many groups of 10, and the ones digit tells how many extra ones.

💡 Say it like: 47 is 4 tens and 7 ones.