Regrouping Four 10'sDate: 10/15/2001 at 19:46:26 From: Lori Subject: Subtraction problem in Math Hi, I'm trying to help my nephew with this math question. How would you regroup four 10's to find the difference between 341 and 228? We know the difference between 341 and 228 is 113. We don't understand the "regoup four 10's" part.Can you help? Thank you! Date: 10/15/2001 at 22:18:33 From: Doctor Peterson Subject: Re: Subtraction problem in Math Hi, Lori. Regouping is what you might know as borrowing. It means that we take the 4 in 341, meaning 4 tens, and think of it as 3 tens and 10 ones: 3 4 1 ---> 3 3 11 - 2 2 8 - 2 2 8 --------- --------- 1 1 3 If we were modeling 341 as 3 groups of 100 sticks, 4 groups of ten, and 1 single stick, this would be literally unbundling and regrouping, as we untied one of the 4 groups and put the ten sticks in with the one. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/ Date: 10/25/2001 at 18:47:31 From: Lori Subject: Re: Subtraction problem in Math Thank you so much! This helps a great deal. |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/