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