An oil merchant wants to make a minimum profit of Rs.2,100 by selling 50 litres of oil he purchased at Rs.236 per litre. For this he adds a few litres of duplicate oil whose cost price is Rs.180 per litre and sells at Rs.250 per litre. How many litres of duplicate oil is needed for this purpose?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e 20 litres
Let the quantity of duplicate oil be 'x' litres.
⇒ 50 × 236 + x × 180 + 2100 = (50 + x) × 250
⇒ 11800 + 180x + 2100 = 50 × 250 + 250x
⇒ 13900 - 12500 = 250x - 180x
⇒ 70x = 1400
⇒ x = 1400/70
⇒ x = 20