Answer:
The common ratio r = 2.
Step-by-step explanation:
Now s2 = a1r and s4 = a1r^3  where a1 = first term and r = common ratio so
s4 / s2 = a1r^3  / a1r = r^2 = 32/8
r^2 = 4
r = 2.
 
        
                    
             
        
        
        
It shoukd be A if im not mistaken
        
             
        
        
        
Answer:
Let the distance of school and house is x k m
Then time taken at speed 2.5 km\hr= 
2.5
x
 
 hr
And time taken at speed 4 km\hr= 
4
x
 
 hr
∴ 
2.5
x
 
 − 
4
x
 
 = 
60
12
 
 ⇒ 
10
4x−2.5x
 
 = 
5
1
 
 ⇒x=3 km
Then the distance of school and house is 3 k m
may this help you