Question

Julian is using a biking app that compares his position to a simulated biker traveling Julian's target speed. When Julian is behind the simulated biker, he has a negative position. Julian sets the simulated biker to a speed of 20\,\dfrac{\text{km}}{\text{h}}20 h km ​ 20, space, start fraction, k, m, divided by, h, end fraction. After he rides his bike for 151515 minutes, Julian's app reports a position of -2\dfrac{1}{4}\,\text{km}−2 4 1 ​ kmminus, 2, start fraction, 1, divided by, 4, end fraction, space, k, m. What has Julian's average speed been so far?

Answer 1

11

Explanation:

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Answer 2

11 km/hr.

Explanation:

Given information:

Simulated speed = 20/km/h

Time = 15 mins = 1/4 hr = 0.25 hr

Distance Covered as per simulated speed =
`20* (1)/(4)=5km`

Position of Julian according to the app =
`-2(1)/(4)=-2.25`.

Actual distance covered by the bike is

`Distance= 5 - 2.25 = 2.75km`

Formula for speed:

`\text{Average Speed}=(Distance)/(Time)`

`\text{Average Speed}=(2.75)/(0.25)`

`\text{Average Speed}=11`

Therefore, the average speed of Julian is 11 km/hr.