Question

In a city, in the year 2019, the price of petrol increased by 25% in the first quarter, increased by 33.33% in the second quarter, fell by 20% in the third quarter and then, again fell by X% in the fourth quarter. If the price of petrol at the end of the fourth quarter was the same as it was at the beginning of the first quarter, then, what is the value of X?
1. 20
2. 24
3. 16.67
4. 25
5. 30

Answer 1

Correct Answer - Option 4 : 25

CALCULATION :

Suppose the price of the petro at the beginning of the first quarter in 2019 be ₹ 100.

According to given conditions –

⇒ 100 × (1+ 25/100) × (1 + 33.33/100) × (1 – 20/100) × (1 – X/100) = 100

⇒ [5/4 × 4/3 × 4/5 × (100 – X)/100] = 1

⇒ 4/3 × (100 – X)/100 = 1

⇒ 4(100 – X) = 300

⇒ 400 – 4X = 300

⇒ 4X = (400 – 300)

⇒ 4X = 100

⇒ X = 100/4

⇒ X = 25%

∴ The value of X is 25.