Skip to 0 minutes and 1 secondHan and Samir had $680 altogether. Han had three times as much money as Samir. If Han spent $135 of his money, how much did he have left? So the bar model can help us visualise quite nicely the relationships between the different amounts on the basis of the information that we have from this problem. So if, say, Samir has this amount of money, we know that Han had three times as much. So if this is how much Samir has then this is how much Han has. And we know that altogether they have £680.
Skip to 0 minutes and 47 secondsNow one important piece of understanding to have while using the bar model is that each of the boxes represents an equal amount, so, if we divide 680 by 4 we should be able to find how much each of the boxes represents.
Skip to 1 minute and 14 secondsSo I’m going to do 680 divided by 4: 4 goes into 6 one time. 1 x 4 = 4. 6 - 4 is 2 and I’m going to bring the 8 down. 4 goes into 28 seven times. 7 x 4 is 28. I’m going bring the zero down and 4 goes into 0 zero times. So 170. So now I know that each of these boxes represents $170 and I know that Samir has $170 dollars, and to find out the total amount of money that Han has, I need to multiply 170 by 3. 3 x 0 is 0. 3 x 7 is 21. 1 x 3 is 3, add the 2 = 5. So I know that Han has $510.
Skip to 2 minutes and 19 secondsNow the problem asks, if Han spent $135 of his money, how much did he have left?
Skip to 2 minutes and 31 secondsSo all I need to do now is the subtraction 510 – 135: 0 – 5: I can’t do that so I’m going to borrow 1 from there and be left with 0 there. 10 – 5 is 5. 0 – 3: I can’t do that so I’m going to borrow from there. 10 - 3 is 7. 4 - 1 is 3. 375 is the answer to my question.
Solution: division word problems
This is a solution video for the previous task where you were asked to complete a division word problem.
The task is:
Han and Samir had $680 altogether. Han had 3 times as much money as Samir. If Han spent $135 of his money, how much did he have left?
Note: This task comes from ‘Max Maths Primary - A Singapore Approach’.
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