As a result of 25% hike in the price of rice per kg

As a result of 25% hike in the price of rice per kg, a person is able to purchase 6 kg less rice for Rs. 1,200. What was the original price of rice per kg?

  1. Rs. 30
  2. Rs. 40
  3. Rs. 50
  4. Rs. 60

Answer: B

Explanation

Method I:

Let the original price be Rs. 100x /kg

Original quantity purchased for Rs. 1200 = 1200/100x = 12/x kg

After 25% hike, the price will be Rs. 125x /kg

Quantity purchased for Rs. 1200 after the hike = 1200/125x = 48/5x kg

According to the question,

(12/x) - (48/5x) = 6

30x = 60 - 48 = 12

x = 2/5 = 0.4

So, original price = 100x = 100 × 0.4 = Rs. 40 per kg

Method II:

Expenditure is constant. So, if the price is increased by 25%, the quantity purchased will decrease by 20%.

As per the question, 20% = 6 kg. So, 100% = 6 × 5 = 30 kg

Hence, original price = Expenditure / Original Quantity

= 1200/30 = Rs. 40 per kg

  • Exam Year: 2020