Correct Answer - Option 3 : 20%
GIVEN:
Marked Price = Rs.150 & Selling Price = Rs.105 and 2nd Discount = 12.5%
FORMULA USED:
MP × (100 - Discount %)/100 = SP
CALCULATION:
Let 1st Discount be x%
⇒ MP × (100 - Discount %)/100 = SP
⇒ 150 × (100 - x)% × (100 - 12.5)% = 105
⇒ 150 × (100 - x)% × 87.5% = 105
⇒ (100 - x) = (105 × 10000)/87.5 × 150
⇒ 100 - x = 80
⇒ x = 20
∴ First Discount is 20%