Correct Answer - Option 2 :
II and III
Given:
D1 = 40%
D2 = 25%
D3 = 5%
Formula Used:
Discount% = (Discount/MP) × 100
SP = {(100 – D%)/100} × MP
Where D is discount, SP is selling price and MP is maximum retail price.
Calculation:
SP after D1 = (60/100) × MP
SP after D2 = (75/100) × (60/100) × MP
SP after D3 = (95/100) × (75/100) × (60/100) × MP
Final SP = (95/100) × (75/100) × (60/100) × MP
⇒ (19/20) × (3/4) × (3/5) × MP
⇒ 42.75/100 MP
Effective discount = (100 – 42.75) %
⇒ Effective discount = 57.25%
I. Effective discount is 60.25%
I is incorrect
II. Effective discount after first two discounts is 55%
(– 40) + (– 25) + {(– 40) × (– 25)}/100
⇒ – 40 – 25 + 10
⇒ - 55 %
⇒ II is correct
III. Effective discount is not integer
Effective discount = 57.25%
⇒ III is correct.
∴ II and III is correct
Short Trick:
Effective discount = 100 – (0.6 × 0.75 × 0.95 × 100)
⇒ 100 – 42.75
⇒ 57.25%