Successive discounts of 10%,12% and 15% amount to a single discount of -

Answer: Option A

Let marked price be Rs. 100
Then,
S.P. = 85% of 88% of 90% of Rs. 100
$$\begin{array}{rl}& =\text{Rs}\text{.}\left(\frac{85}{100}\times \frac{88}{100}\times \frac{90}{100}\times 100\right)\\ & =\text{Rs}.67.32\end{array}$$
∴ Single Discount
= (100 - 67.32)%
= 32.68%