Simply it as follows:
1 + 39 = 40
2 + 38 = 40 etc
18 + 22 = 40
19 + 21 = 40
There are 19 of these plus 40 itself . . .therefore 20 of them
20 x 40 = 800
And finally the last number not used, 20
Therefore 800 + 20 = 820
        
                    
             
        
        
        
Answer:
The answer is B or 8
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
54 lbs.
Step-by-step explanation:
7 x 6 = 42
3 x 4 = 12
42+12=54
 
        
             
        
        
        
Answer: n=
−28
/61
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
a) 675 000
b) 685 000
Step-by-step explanation:
The population of a town is 680 000 correct to the nearest 10 000.
a) To find it lower bound, we level of accuracy by 2 and then subtract from 680 000
The lower bound is:
680 000-5000=675,000
Therefore the least possible population of the town is 675 000
b) We repeat the same process to find the upper bound
680 000+5000=685,000