Question

If the diameter of the dart board is 42 centimeters, what is the approximate circumference?

Answer 1

131.88 cm or 132 cm

Explanation:

Circumference - diameter times pi

`C = dpi`

`C = 42pi`

`C=42(3.14)`

`C = 131.88 cm`

Answer 2

A quick estimate gives `1.2m`, a bit more accurate is `1.26m`

Explanation:

The word to note here is "approximate".

This implies that an accurate calculated answer with exact values is not required, but rather just a quick estimate.

The diameter is 42cm - that's close to 40cm

The value of `pi` is 3.142 - that's close to 3.

`C = piD`

The circumference is about `40 xx 3 =120cm = 1.2m`

A closer estimate would be `42 xx3 = 126cm`

Answer 3

`132` `cm`

Explanation:

We know that the diameter is `42` `cm`

We need to find the circumference of the circle, we use

`color(blue)("Circumference="pid`

Where,

`color(brown)(pi~~22/7`

`color(brown)(d="diameter"=42` `color(brown)(cm`

`rarrpid`

`rarr22/7*42`

`rarr22/cancel7^1*cancel42^6`

`rarr22*6`

`rArrcolor(green)(132` `color(green)(cm`

An accurate answer would be `131.88` (multiplying `42` with `3.14`)