Question

Shaad lives in Lucknow. He wants to go Aminabaad for shopping from Chowk. He uses his Bullet for the same. The Bullet runs at the rate of 60 kmph and reaches Aminabaad 20 minutes earlier of schedule. After shopping, when he was returning back to Chowk, his Bullet runs at an average speed of 20 kmph, he reaches 30 minutes late. What is the distance between Aminabaad and Chowk ?
1. 30 km
2. 35 km
3. 20 km
4. 25 km

Answer 1

Correct Answer - Option 4 : 25 km

Given∶

Speed of Bullet while going to Aminabaad = 60 kmph, at this speed he reaches 20 min. or 1/3 hr earlier.

Speed of Bullet while going back to Chowk = 20 kmph, at this speed he reaches 30 min. or 1/2 hr late.

Formula Used∶

Time = Distance / speed

Calculation∶

Let the distance between Chowk and Aminabaad be x km

And, the speed in order to reach on time is y kmph.

SO, time taken to reach on schedule will = x/y hours

A.T.Q.,

x/60 = x/y - 1/3   

x/20 = x/y + 1/2    

Solving above equations, we get

(x/20) - (x/60) = 1/2 + 1/3

⇒ (3x - x)/60 = 5/6

⇒ 2x = 5 × 60/6

⇒ x = 25 km

∴ The distance between Aminabaad and Chowk is 25 km.