Video Transcript
The number of houses built in one state was 33726, while 47612 houses were built in another. What is the difference between the number of houses built in the two states?
When a question asks us to find the difference between two amounts, we’re to count on. Or we can subtract to find the answer. We’ve been given two five-digit numbers that represent the number of houses built in two different states, 33726 and 47612. These numbers don’t look like they’re going to be easy to count on from one to the other. So perhaps, the best way to find the answer is to subtract one from the other. So let’s find the difference using columns subtraction.
First, we need to write one number on top of the other and make sure that we put the larger number first. The second thing to make sure is that all of our digits are lined up, so they’re in the correct columns when it comes to subtract them. What’s two ones take away six ones? But we can’t do this. Six is greater than two. But we know we can take six ones away from the number because we’ve got 47612.
What we need to do is to write the number slightly differently. We can take one ten from the tens columns — so instead of one ten, we’ve now got zero tens — and exchange it for ten ones. The whole number is still worth the same. But we’ve just juggled it around slightly. We now can subtract the ones. 12 ones take away six ones leaves us with six ones. On to the tens column. Zero tens take away two tens, but we can’t do this. So okay, we’re going to have to exchange. We’re gonna take one hundred from the hundreds column instead of six hundreds. We’ve now got a five hundreds. And we’re gonna exchange it for 10 tens.
So we now have 10 tens in the tens column. 10 tens take away two tens leaves us with eight tens. We’re going to have to exchange again in the hundreds column because seven is larger than five. So we’ll take one thousand from the thousands columns instead of seven thousands. We now have six thousands. And we’re gonna exchange it for 10 hundreds. We now have 15 hundreds. 15 hundreds take away seven hundreds leaves us with eight hundreds.
On to the thousands, six thousands take away three thousands leaves us with three thousands. And finally, four 10 thousands take away three 10 thousands leaves us with one lot of 10 thousands. We used column subtraction to find the answer. If the number of houses built in one state is 33726, while 47612 houses are built in another state, the difference between these two numbers of houses built is 13886.
