About this video
Charles buys 5 apples at 47 cents each and pays with a five-dollar bill. The video works in cents: the apples cost 5 x 47 = 235 cents, the bill is 500 cents, and 500 - 235 = 265 cents of change, which is $2.65.
You'll be able to
- change dollars into cents using 100 cents per dollar.
- find the total cost of several items and the change from a payment.
- write an amount in cents as dollars and cents, like 265 cents = $2.65.
Key words
- cent
- A small unit of money; 100 cents make 1 dollar.
- change
- The money you get back when you pay more than something costs.
- regrouping
- Trading one of a bigger place value for ten of the next smaller one so you can subtract.
Transcript
Charles bought 5 apples that cost $0.47 each. He paid with a five-dollar bill. How much change did Charles receive? So let's think about everything in cents since they gave us the cost in terms of cents. So first of all, how much would the 5 apples cost? Well, we got 5 apples.
5 apples-- let me do that same green color. We have 5 apples, and each of those apples are going to cost $0.47. So 5 apples times $0.47 per apple, this will give us the total cost of the 5 apples in cents. So what's 5 times 47? Well, let's see. 5 times 40 is 200.
5 times 7 is 35. So it's going to be 235 cents. So it's 235. And just to remind ourselves, this is 235 cents. Now, how much did he pay? He paid with a five-dollar bill. Well, a five-dollar bill is going to be how many cents? Well, let's think about it. A five-dollar bill times 100 cents per dollar, he's essentially paying with 500 cents.
So this right over here is the cost, and then this is what he paid. So we could figure out how much change he needs to get back in terms of cents. So he paid 500. The cost was 235. 235, so we just need to subtract. And you might be able to do this in your head.
But in case you can't, we can solve this. We can do this by regrouping. We have a 0 in the ones place. We have a 0 in the tens place. But let's try to regroup from the hundreds place. We could take one of the hundreds, so now we have only 400 left. And a hundred is equal to 10 tens.
So we could put a 10 in the tens place. But then we could take one of those tens away, so we only have 9 tens. And if you took a 10 away, then you put that in the ones place, it's going to become a 10. And now we're ready to subtract. So we are left with 10 minus 5 is 5.
9 minus 3 is 6. 4 minus 2 is 2. So how much change does Charles receive? Well, it would be 265 cents. If we wanted to write this in terms of dollars, we already know that there are 100 cents per dollar. So you could view this as 200 cents plus 65 cents. And 200 cents-- well, this is two groups of 100 cents, or $2.
So this right over here is $2 and 65 cents. Or you could view this-- because 65 cents is really 65 hundredths of a dollar. You could view this as $2 and 65/100 of a dollar, or $2.65. So that's how much change Charles should receive.
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