# Question Video: Subtracting Tens from Three-Digit Numbers Using Partial Difference Mathematics

Find the difference by first subtracting tens. 386 − 50 = ＿

02:05

### Video Transcript

Find the difference by first subtracting tens. 386 take away 50 equals what?

In this problem, we need to find the difference between 386 and 50, which means that we need to take away 50 from 386. And, the way we’re told to do this is by first subtracting tens. If we look carefully at the calculation, we can see that the first number has been broken down or partitioned. The number 386 has three hundreds, eight tens and six ones. And we need to take away 50 which is worth five 10s. We already have eight 10s. So, the number 386 has bean broken apart to take the tens out, so that we can just subtract the tens first. So, this is why our part whole model at the top shows that it’s been split into 306 and 80.

Now, we can subtract the tens. We know that eight take away five equals three. And so, eight 10s take away five 10s equals three 10s. Or in other words, 80 take away 50 leaves us with 30. We started off with eight 10s. We took away five 10s. And now, we have three 10s. We’ve subtracted the tens. So now, to find the overall answer, we need to combine the tens back with the other part. 306 plus 30 equals 336. We found the difference by first subtracting tens. 80 take away 50 equals 30. And so, 386 take away 50 equals 336.