Video Transcript
Solve the following: 402 subtract
34 equals what.
In this question, we have to
subtract 34 from 402 using the standard written method. Let’s model the number that we’re
subtracting from using some place value counters. The number 402 has four 100s, and
we’ve modeled this using four 100s counters. 402 doesn’t have any tens, so we
have no counters to place in the tens column. And we have a two digit in the ones
place, which we’ve modeled using two ones counters. Now we can start subtracting.
Remember, we always start in the
ones place: two subtract four. We have a bit of a problem. We don’t have enough ones. We’ve got two ones, and we need to
subtract four. Monster’s right; we need to
regroup. We could take one 10 and exchange
it for 10 ones. But wait! There are no tens to exchange. So we’re going to have to move to
the hundreds column. We need to take one of our hundreds
and exchange it for 10 10s.
Now we’ve got three 100s, 10 10s,
and two ones. But we still don’t have enough ones
to subtract four from. We need to regroup again. We need to take one of our
tens. Now we’ll have nine 10s left. And we need to exchange our 10 for
10 ones. Now we have 12 ones. Now we can start to subtract. 12 take away four is eight. Nine 10s subtract three 10s is six
10s. And there’s nothing to subtract
from our three 100s. 402 subtract 34 is 368. To find the answer, we had to
regroup twice. But we used our place value
counters to help. 402 subtract 34 is 368.
