# Two elements A (atomic weight = 75) and B (atomic weight = 16) combine to yield a compound. The % by weight of A in the compound was found to be 75.08 . The formula of the compound is :

$\begin{array}{1 1}(a)\;A_2B&(b)\;A_2B_3\\(c)\;AB&(d)\;AB_2\end{array}$

Molecular weight of $A_2B_3=75\times 2+16\times 3=198$
198g of $A_2B_3$ =150g of A
$\therefore$ 10g of $A_2B_3=\large\frac{150\times 100}{198}$ = 75.08g of A
Hence (b) is the correct answer.
edited Mar 18, 2014