Question

An athlete ran a sprint of 100 ft in 3.1 s. At what speed was the athlete running in miles per hour? Round to the nearest mile per hour.

Answer 1

Answer:

22 miles per hour

Step-by-step explanation:

we know that

The speed is the ratio of distance by the time

Let

d -----> distance in feet

t ----> time in seconds

s ----> the speed in ft/sec

$s=\frac{d}{t}$

we have

$d=100\ ft\\t=3.1\ sec$

substitute

$s=\frac{100}{3.1}$

$s=32.26\frac{ft}{sec}$

Remember that

$1\ mi=5,280\ ft$

$1\ h=3,600\ sec$

Convert ft/sec to mi/h

$s=32.26\frac{ft}{sec}=32.26\frac{(1/5,280)}{(1/3,600)}=32.26(\frac{3,600}{5,280})=22\ \frac{mi}{h}$