1 / 12

Mental Math Day 1

Mental Math Day 1. Basic Addition. Add and subtract the summands to make this easier! 1202 + 998 = ? + 1000 = 1200 + 1000 = 2200. More Basic Addition. 5346 + 445 = ? + 450 = 5341 + 450 = 5741+50 = 5791. -. +. SUMMAND 1. SUMMAND 2. You try it! (all techniques).

susan
Download Presentation

Mental Math Day 1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Mental MathDay 1

  2. Basic Addition • Add and subtract the summands to make this easier! 1202 + 998 = ? + 1000 = 1200 + 1000 = 2200

  3. More Basic Addition 5346 + 445 = ? + 450 = 5341 + 450 = 5741+50 = 5791 - + SUMMAND 1 SUMMAND 2

  4. You try it! (all techniques) • 87654321+12345678= • 123456789+987654321= • 1+2+3+4+5+6+7+8+9= =(1+9)+(8+2)+(7+3)+(6+4)+5= • 2+4+6+8+10+12+14+16+18=

  5. Sum all entries - Which is More?

  6. SUM All ENTRIES

  7. Total is 10x55+100x45

  8. Total is 10x55+100x45=550+4500=5000+50=5050

  9. Add up all the numbers in this table (in your head!)

  10. Sum is 55x55 + 55+55=? 55 more

  11. Sum is 55x55 + 2x55=? =(50+5)x(50+5)+2x55 =(50x50)+5x50+50x5+5x5+2x55 So we need the total of • 2500 • 250 • 250 • 25 • 110

  12. Sum is 55x55 + 55=? So we need the total of • 2500 • 250 • 250 • 25 • 110 This is 2500+500+135=3135

More Related