# Question Video: Subtracting Tens from a Three-Digit Number by Breaking Parts Mathematics

Look at how Jennifer broke apart a number to subtract. 473 − 30 = ＿. First, subtract the tens: 70 − 30 = ＿. Then, add the leftover tens to 403 to find 473 − 30.

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### Video Transcript

Look at how Jennifer broke apart a number to subtract. 473 take away 30 equals what. First, subtract the tens: 70 take away 30 equals what. Then, add the leftover tens to 403 to find 473 take away 30.

Jennifer is trying to find the answer to a subtraction, 473 take away 30. Now, we know that 473 contains four hundreds, seven tens or 70, and three ones. Now, the number that she needs to subtract is 30. And 30 is the same as three tens. Because Jennifer needs to subtract a number of tens from her three-digit number, she breaks apart her number to separate out the tens. And the first part of our problem asked us to look at how she breaks apart her number to subtract.

She starts off with 473. And then, she draws this part-whole model here to show how she split up the number. On the right are her seven tens. And on the left is the remaining part of the number, which is 403. Now that she’s broken apart her number, she’s ready to subtract. And in the first part of the problem, we’re asked to subtract the tens. The 70 that Jennifer has broken apart take away 30. Let’s subtract three tens from our seven tens. One, two, three. We have four tens left. Seven take away three equals four. And so, seven tens take away three tens leaves us with four tens or 40.

But is 40 the answer to our problem? It is the difference between 473 and 30. No, it’s not. Remember, Jennifer broke apart her number. We need to put it back together again now. We’re asked to add the leftover tens to 403 to find the answer, 473 take away 30. Let’s combine our two parts back together again. The answer is going to have four hundreds instead of seven tens. There are now four tens or 40 and, of course, three ones. 403 plus 40 equals 443. We started off with a number with seven tens. We subtracted three tens. And we ended with a number with four tens. 473 take away 30 equals 443.