Question

What is the diameter of a circle whose circumference is 5?

Answer 1

`"diameter "=5/pi~~1.59" to 2 dec. places"`

Explanation:

`"the circumference (C) of a circle is"`

`•color(white)(x)C=pidlarrcolor(blue)"d is the diameter"`

`"here "C=5`

`rArrpid=5`

`"divide both sides by "pi`

`(cancel(pi) d)/cancel(pi)=5/pi`

`rArrd=5/pi~~1.59" to 2 dec. places"`

Answer 2

The diameter is `35/22`.

Explanation:

The diameter of a circle is twice its radius.

We can find the radius of the circle by the equation

`"circumference" =2pir`

Now, just plug it in as `5 = 2pir`

`5=2*(22/7)r`

`r = 5*(1/2)*(7/22)`

`r = 35/44`

Since the diameter is twice the radius, `d = 35/44 * 2`

`d=35/22`