Video Transcript
Complete the following. 70 subtract 50 equals what.
We can model the number 70 using
10s blocks. How many 10s do we need to make the
number 70? There are seven 10s and no
ones. 10, 20, 30, 40, 50, 60, 70. We have to subtract 50. If we subtract 10, we’re left with
60. We subtracted two 10s, which is
20. Now, we’ve subtracted 30, 40,
50. We had seven 10s. We subtracted five 10s. And we’re left with two 10s. Two 10s are 20. So, 70 subtract 50 equals 20.