Question

What is the average speed of a biker if she biked 4 1/4 of a mile in 25 minutes?

Answer 1

Answer:

$\frac{10.2\text{ miles}}{\text{ hour}}$

Step-by-step explanation:

We are asked to find the speed of a biker, who biked 4 1/4 of a mile in 25 minutes.

To find average speed of the biker, we will divide total distance by total time taken.

$4\frac{1}{4}\text{ miles}\div 25\text{ min}$

Convert mixed fraction into improper fraction:

$4\frac{1}{4}\Rightarrow \frac{4*4+1}{4}=\frac{16+1}{4}=\frac{17}{4}$

$\frac{17}{4}\text{ miles}\div \frac{25}{1}\text{ min}$

Convert to multiplication problem by flipping the 2nd fraction:

$\frac{17}{4}\text{ miles}\times \frac{1}{25\text{ min}}$

$\frac{17\text{ miles}}{100\text{ min}}$

Convert minutes to hour:

$\frac{17\text{ miles}}{100\text{ min}}\times \frac{\text{60 min}}{\text{1 hour}}$

$\frac{17\text{ miles}}{10}\times \frac{6}{\text{1 hour}}$

$\frac{102\text{ miles}}{\text{10 hour}}$

$\frac{51\text{ miles}}{\text{5 hour}}$

$\frac{10.2\text{ miles}}{\text{ hour}}$

Therefore, the average speed of biker is 10.2 miles per hour.

Answer 2

Answer:

Step-by-step explanation:

What is the average speed of a biker if she biked 4 1/4 of a mile in 25 minutes?

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rate = distance/time

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rate = (17/4)/(25/60) = (17/4)(60/25) = (17*3/5) = 51/5 = 10.2 mph

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