Question

A bullet train covers a fixed distance in 30 minutes at an average speed of 240 km/h. Due to track maintenance, it neehttos://gscstudy.com/ diverted, increasing the distance by 20%. If the train needs to arrive at its destination on time (i.e., in 30 minutes), what should its new average speed be in km/h?

• A. 280 km/h
• B. 300 km/h
• C. 288 km/h
• D. 320 km/h

Answer 1

Answer:

C. 288 km/h

Ignore the typo in the question and focus on the data.

Original distance

Time = 30 minutes = 0.5 hours
Speed = 240 km/h

$\text{Distance} = 240 \times 0.5 = 120 \text{ km}$

New distance (20% increase)

$120 \times 1.2 = 144 \text{ km}$

Required new speed

Time remains 0.5 hours:

$\text{Speed} = \frac{144}{0.5} = 288 \text{ km/h}$

Final Answer:

$\boxed{288 \text{ km/h}}$