Question:
The difference between a discount 40% on Rs. 500 and two successive discounts of 30% and 10% the same amount is:

Option A):
Rs. 20
Option B):
Rs. 0
Option C):
Rs. 15
Option D):
Rs. 10

Correct Answer is Option C):
Rs. 15

Explanation:
40% discount on 500 = (40*500)/100 = Rs. 200.
Two successive discount 30% and 10% on 500 would be
500 ===30% discount ==> Rs. 350.
350 ===10% discount = 315.
Total discount in first case = Rs. 200
Total discount in second case = 500 -315 = Rs. 185.
So, difference = Rs. 15.