WEBVTT
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345 take away 60 equals what?
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We could answer this calculation mentally.
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To help us visualize the problem, we could use a number line.
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We start at number 345.
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We need to subtract 60 to give us the answer or the missing number.
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We could do this in steps.
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First, we can take away 45.
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345 take away 45 takes us to 300.
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We have to take away a total of 60.
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We’ve already taken 45.
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So the difference between 60 and 45 is 15.
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This means we have to take away another 15.
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We could subtract 15 by first subtracting five and then subtracting 10.
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300 take away five is 295.
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Now, we need to calculate 295 take away 10, which is 285.
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We found our answer.
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We could also use a written method to help us calculate the answer.
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We could use column subtraction.
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Starting in the ones place, five take away zero is five.
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And in the tens column, we’re subtracting 60 from 40.
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We don’t have enough tens.
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40 is less than 60.
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So we need to borrow a 10 from the hundreds column.
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So now we have two hundreds left in the hundreds column and we have 14 tens in the tens column.
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14 take away six is eight.
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Now, we can move into the hundreds column.
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Two take away nothing is two.
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We get the same answer of 285 using both methods.
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To subtract mentally, we counted back 60 from 345 and we also used the column subtraction method.
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We could use either of these methods to help find the answer or you may have one of your own.
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Both methods still give us the answer 285.