Question

an object travels 4/5 miles in one half hour. What is its speed?

Answer 1

So,

If you mean "speed per hour," then we just have to double the numerator of the fraction.
4 * 2 = 8

The object's speed is 8/5 miles per hour or 1.6 mph.

Answer 2

By definition, the speed of an object is given by:

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

Where,

d: distance traveled by the object

t: time it takes the object to travel the distance

Substituting values we have:

$s =\frac{\frac{4}{5}}{\frac{1}{2}}$

$s = \frac{8}{5} mph$

Answer:

The speed of the object to travel 4/5 miles in half an hour is:

$s = \frac{8}{5} mph$