? % of 450 + 46% of 285 = 257.1

A. 31

B. 28

C. 32

D. 34

Answer: Option B

Solution(By Examveda Team)

Let x% of 450 + 46% of 285 = 257.1
$$ \Rightarrow \left( {\frac{x}{{100}} \times 450} \right) + \left( {\frac{{46}}{{100}} \times 285} \right)$$     $$ = 257.1$$
$$\eqalign{ & \Rightarrow \frac{{9x}}{2} = 257.1 - 131.1 \cr & \Rightarrow \frac{{9x}}{2} = 126 \cr & \Rightarrow x = \frac{{126 \times 2}}{9} \cr & \Rightarrow x = 28 \cr} $$