Let's work on writing tens numbers. Remember, tens numbers have a zero in the ones place (ones column). One ten equals 10, with 1 in the tens place (tens column) and 0 in the ones place.
Let's start with the value 8 tens. We only have to write 8 in the tens place and then write a 0 in the ones place.
We read the value as eighty.
Our next value is 13 tens. Now, we can't write 13 in the tens place. We must write the number so that the ones digit of 13 is in the tens place, so we write 3 in the tens place. We will write the 1 from 13 in the hundreds place (hundreds column). Then we write 0 in the ones place.
We read 13 tens as one hundred thirty.
For our last example, our value is 72 tens. Because we can't write 72 in the tens place, we write the number so that the ones digit is in the tens place and the tens digit is in the hundreds place. Then we add 0 in the ones place.
We read 72 tens as seven hundred twenty.
