The marked price and cost price of a book are Rs 850 and Rs 748 respectively. The discount in percentage is?

**(a) 12%**

(b)10%

(c)15%

(d)8%

To find the discount percentage, you can use the formula:

\[ \text{Discount Percentage} = \left( \frac{\text{Marked Price} – \text{Cost Price}}{\text{Marked Price}} \right) \times 100\]

Given that the marked price (\(MP\)) is Rs 850 and the cost price (\(CP\)) is Rs 748:

\[ \text{Discount Percentage} = \left( \frac{850 – 748}{850} \right) \times 100 \]

\[ \text{Discount Percentage} = \left( \frac{102}{850} \right) \times 100 \]

\[ \text{Discount Percentage} \approx 12\% \]

Therefore, the discount percentage is approximately 12%.