الثلاثاء، 7 يونيو 2016

Subtracting Two Digit Numbers with Regrouping (Borrowing)



Let's just dive right in and do one!


Just like before, stack and line things up:



<< Now, I'm going to make my stripes taller...

You'll see why in a second!


The first thing to do is to subtract the ones... But, there's a big problem!




But, no worries... We can fix it! What we're going to do is borrow from the tens stripe. (Also called regrouping!) This is going to look funky at first, but you'll get it pretty easily after you do some of them. It's not that bad. Trust me! It's also a really good idea to grab a pencil or, even better, some colored markers and work these along with me!

Head on over to the next page and we'll get to work!







Here's how we're going to do it:


Now, remember, that's really 90 = 80 + 10!

Now, here's the key to this whole trick:



A 1 in the tens stripe is 10...
and that's the same as 10 ones!


< It's just like swapping a $10 bill for ten $1 bills! >



Now, add the 10 and the 2 in the ones stripe:



Now, we'll finish it off quick! 

Subtract the ones... Then, subtract the tens...










Go to the next page for another one... It's going to feel a LOT easier the second time!

ليست هناك تعليقات:

إرسال تعليق

المشروعات البحثية للمراحل التعليمية الاساسية

أحصل على القوالب الخاصة بالمشروعات البحثية للمراحل التعليمية الاساسية من خلال هذا الرابط Get templates for research projects for basic edu...