### Video Transcript

Subtracting Ones from Teen
Numbers

In this video, we will learn how to
subtract a one-digit number from a teen number. We can make teen numbers from a 10
and some ones. 11 is a teen number. We can break this number apart into
a 10 and one one. 10 and one makes 11. We could make the number 19 from a
10 and nine ones. In this video, we’re going to learn
how to take away ones from a teen number. 19 is a teen number, and teen
numbers have two digits. They have a tens digit and a ones
digit.

The number six only has one
digit. This digit is its ones. So we’re going to be taking away
ones from a two digit-number which has tens and ones. So we’re going to be taking away
from the ones digit. To take away six from 19, we need
to take away six ones. One, two, three, four, five,
six. Did you notice how the ones were
decreasing? We had nine ones. We took away six. Now we have three ones left. 10 and three ones is 13. So 19 take away six equals 13. Let’s try some practice
questions.

Daniel drew this model to help him
subtract. Which of these has the same answer
as 16 take away five? Is it 10 plus one, 10 plus five, or
one plus one? What is 16 take away five?

Daniel is trying to find the answer
to 16 take away five. He’s used ten frames to make a
model of the number 16 using a 10 and six ones. He’s taken away five of his ones,
which leaves him with 10 and one. 10 and one makes 11. We’ve answered the first part of
the question. Daniel’s model shows 10 plus
one. 10 plus one gives us the same
answer as 16 take away five. We know that 10 plus one is 11, so
16 take away five is 11.

What is 13 take away three?

Let’s look closely at the model
which has been drawn to help us. 13 is a teen number; it’s made from
a 10 and three ones. 10 and three makes 13. We’re taking a one-digit number,
number three, away from a two-digit number, number 13. And the model is telling us to take
away the ones first. There are three ones in 13, and we
have to take away three ones. What is three take away three?

If we take away our three counters,
which represent our three ones, we have no ones left. Three take away three equals
zero. Now, we’re left with a 10 and no
ones. 10 plus zero is 10. So 13 take away three equals
10.

Fill in the blank. 16 take away four equals what.

The number 16 is a two-digit
number. We can break it apart into 10 and
six ones. We have to take away four. Four is a one-digit number. Its digit represents the number of
ones it has. So we just need to take away four
ones from our six ones. Now, we have a 10 and two ones. 10 and two is 12. 16 take away four equals 12. The missing number is number
12.

What have we learned in this
video? We’ve learned that when we subtract
a one-digit number from a teen number, we can break the teen number apart into tens
and ones and then subtract the ones.