20 kg of rice costing ₹80 per kg is mixed with y kg of rice costing ₹100 per kg. If the cost of this mixed rice is ₹84 per kg, what is the value of y?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 5.
Cost of first type rice = 20 × 80 = 1600
Cost of second type rice = 100y
(1600 + 100y)/(20 + y) = 84
⇒ 1600 + 100y = 1680 + 84y
⇒ 16y = 80
⇒ y = 5