I would recommend asking a tutor
        
                    
             
        
        
        
2 hundreds be cause there are 2, and you are trying to find hundreths so take the first number
        
             
        
        
        
The elephant lost 4 pounds each month. Because he is losing weight, and not gaining weight, you have to make the answer negative
        
             
        
        
        
Answer B. 
∑fx=1637,∑fx 
2
 =127663,∑f=21
x
ˉ
 =Mean= 
∑t
∑fx
	
 =77.95
σ 
2
 = 
∑f
∑fx 
2
	
 −( 
x
ˉ
 ) 
2
 = 
21
127663
	
 −(77.95) 
2
 =2.987
σ=1.728