Posted by MONA on Monday, September 21, 2009 at 8:57pm.
USE MENTAL MATH TO ADD OR SUBSTRACT: USING COMPATIBLE NUMBERS
1. 80+79+20
2. 308+95+5
3. 480+255+20
4.365+289
5. 523198
6. 537+180
7. 325+239+75
8. 87+38+62
9. 4500280

GRADE 5 MATHS  Ms. Sue, Monday, September 21, 2009 at 9:00pm
What are your answers???
We'll be glad to check them for you.

GRADE 5 MATHS  MONA, Monday, September 21, 2009 at 9:09pm
1. 80+79+20=100+20+59=120+59=179
2. 308+95+5=300+100+8=400+8=408
3. 480+255+20=480+20+255=500+255=755
4. 523198=500200=300 AND 23+2=25 THUS 300+25=325

GRADE 5 MATHS  Ms. Sue, Monday, September 21, 2009 at 9:12pm
The first three are right.
You didn't do # 4.
Number 5 is correct.
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