Posted by MONA on .
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,
What are your answers???
We'll be glad to check them for you. 
GRADE 5 MATHS 
MONA,
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,
The first three are right.
You didn't do # 4.
Number 5 is correct.