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8 votes
Alex drives at an average speed that is 2/5 of the average speed that Roy's train travels. Alex takes 30 minutes to travel 50 km in her car. Roy travels for 1 hour and 20 minutes on his train. How far does Roy travel to 2 dp (decimal places)?

User Tsering
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1 Answer

16 votes
16 votes

Answer: 333.33km

Explanation:

Average speed is calculated as:

= Distance / Time

Since Alex takes 30 minutes to travel 50 km in her car, Alex average speed will be:

= 50km / 30minutes

= 50km / 0.5hour

= 100km/hour

Since Alex drives at an average speed that is 2/5 of the average speed that Roy's train travels. Roy's average speed will be:

= 100 ÷ 2/5

= 100 × 5/2

= 250km/hour

Since Roy travels for 1 hour and 20 minutes on his train, his distance travelled will be:

= Speed × Time

= 250 × 1 hour 20 minutes

= 250 × 1 20/60

= 250 × 1 1/3

= 250 × 4/3

= 1000/3

= 333.33km

Roy travels 333.33km

User AdityaParab
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