In the expression xy^{2}, the values of both variables x and y are decreased by 20%. By this, the value of the expression is decreased by 


(a) 
40% 
(b) 
48.8% 
(c) 
51.2% 
(d) 
80% 
In the expression xy^{2}, the values of both variables x and y are decreased by 20%. By this, the value of the expression is decreased by 


(a) 
40% 
(b) 
48.8% 
(c) 
51.2% 
(d) 
80% 
Let X and Y denote the new values of and respectively.
Then, X = 80% of Y =80% of
Decrease in the value = .
Decrease % = % = 48.8%.