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. 523-198

6. 537+180

7. 325+239+75

8. 87+38+62

9. 4500-280

- 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. 523-198=500-200=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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