Question

The average weight of $16$ boys in a class is $50.25kg$ and that of the remaining $8$ boys is $45.15kg$. Find the average weights of all the boys in the class.

• A. $47.55kg$
• B. $48kg$
• C. $48.55kg$
• D. $49.25kg$

Answer 1

The correct option is C $48.55kg$

$\Rightarrow$ The average weight of $16$ boys in a class $=50.25kg$

$\Rightarrow$ The average weight of $8$ boys in class $=45.15kg$

$\Rightarrow$ Required average $=\left(\frac{50.25\times 16+45.15\times 8}{16+8}\right)$

$\Rightarrow$ Required average $=\left(\frac{804+361.20}{24}\right)$

$\therefore$ Required average $=\left(\frac{1165.20}{24}\right)=48.55kg$