Question

a biker must circle a 12 mile track twice. His average speed must be 60mph. On his first lap he averaged 50 mph. How fast must he travel on his second lap to qualify?

Answer 1

Answer:

75 mph

Step-by-step explanation:

A biker must circle a 12-mile track twice. His average speed must be 60 mph.

So, the average time required to cover the distance is $\frac{2 \times 12}{60} = 0.4$ hours.

Now, on his first lap, he averaged 50 mph.

So, he covered this 12 miles track in $\frac{12}{50} = 0.24$ hours.

Hence, he has to cover the next 12 miles track in (0.4 - 0.24) = 0.16 hours.

Therefore, his average speed in the second round must be $\frac{12}{0.16} = 75$ mph to qualify. (Answer)