This chapter looks at how to subtract a multiple of $$10 from a two digit number.
What does a multiple of $$10 look like?
Well if you have more than one $$10 grouped together, you have a multiple of ten. $$2 tens added together are $$20, so $$20 is a multiple of $$10.
If I have $$5 tens I had $$10+10+10+10+10 to get $$50, $$50 is also a multiple of ten.
How do we subtract multiples of ten from a $$2 digit numbers.
Well we have to consider the place values, the tens and the ones (or units).
There are $$2 ways we could subtract the multiple of ten from the two digit number. We could take each ten away one at a time, so $$32−20 is the same as $$32−10−10.
My first step is $$32−10 which is $$22, then my next step is $$22−10 which is $$12. So $$32−20=12.
The second way we can subtract multiples of ten is to align our 2 numbers in place values. We then subtract the ones, and then the tens. Here is what 46 - 30 looks like.
Watch the video below to see how we can do these 2 ways.
Tens | Units | |
---|---|---|
$$4 | $$6 | |
- | $$3 | $$0 |
= | $$1 | $$6 |
Find the value of $$90−10?
Create a pattern by subtracting $$10 each time.
$$90, $$, $$, $$, $$, $$
Complete the number sentence below to make it true.
$$48−=18