### 30 pens and 75 pencils altogether were purchased for Rs. 510. If the average price of a pencil was Rs. 2, what was the average price of a pen ?

A. Rs. 9

B. Rs. 10

C. Rs. 11

D. Rs. 12

$\begin{array}{l}\text{According to the question,}\\ \text{30 pens + 75 pencils}=\text{Rs.}\ 512\\ \text{Average price of a pencil = Rs. 2}\\ \text{Price of 75 pencils}\\ \text{= 2 × 75 = Rs. 150}\\ \text{∴ Price of 30 pens}\\ \text{= 510 – 150 = Rs. 360}\\ \text{∴ Average price of pen}\\ =\Large\frac{360}{30}\\ =\text{Rs.}\ 12\end{array}$