Mental math: Add and subtract multiples of 100
In this math lesson for 2nd grade, I show how easy it is to add and subtract whole hundreds (numbers such as 200, 500, 600, etc.) to any other 3-digit number. It really is so easy that Mathy, my mascot, at one point asks for a more difficult problem - so I provide one for him. :)
Of course, adding and subtracting multiples of 100 mentally is based on place value... we only need to "worry about" the hundreds digit changing in the result.
If you cannot see the video above, click here for an alternative video player.
See also
Add and subtract multiples of ten from 3-digit numbers (mental math)
Mental addition - add a 2-digit and a 1-digit number (with regrouping)
Math Mammoth Grade 2 curriculum
Receive my monthly collection of math tips & resources directly in your inbox — and get a FREE Math Mammoth book!
You can unsubscribe at any time.
Math Mammoth TourConfused about the different options? Take a virtual email tour around Math Mammoth! You'll receive: An initial email to download your GIFT of over 400 free worksheets and sample pages from my books. Six other "TOURSTOP" emails that explain the important things and commonly asked questions concerning Math Mammoth curriculum. (Find out the differences between all these different-colored series!)This way, you'll have time to digest the information over one or two weeks, plus an opportunity to ask me personally about the curriculum. A monthly collection of math teaching tips & Math Mammoth updates (unsubscribe any time) We respect your email privacy.
Note: You will FIRST get an email that asks you to confirm your email address. If you cannot find this confirmation email, please check your SPAM/JUNK folder. |
"Mini" Math Teaching CourseThis is a little "virtual" 2-week course, where you will receive emails on important topics on teaching math, including:
- How to help a student who is behind You will also receive: A GIFT of over 400 free worksheets and sample pages from my books right in the very beginning.
A monthly collection of math teaching tips & Math Mammoth updates (unsubscribe any time)
We respect your email privacy.
Note: You will FIRST get an email that asks you to confirm your email address. If you cannot find this confirmation email, please check your SPAM/JUNK folder. |
Maria's Math TipsEnter your email to receive math teaching tips, resources, Math Mammoth news & sales, humor, and more! I tend to send out these tips about once monthly, near the beginning of the month, but occasionally you may hear from me twice per month (and sometimes less often). Peek at the previous tips here. You will also receive:
We respect your email privacy.
|
|