# Question #a078d

##### 2 Answers

see explanation

#### Explanation:

A: circumference formula:

therefore,

so, for circle A, you get:

for circle B, you get:

B: area formula:

therefore,

for circle A, you get:

for circle B, you get:

C: You observe that the value of pi is the same in all cases. The value of pi is a CONSTANT.

GOOD LUCK

#### Explanation:

**a)**

We need to find a value of

For Circle A:

For Circle B:

**b)**

We aren't given the radius of the circle in each case, but the diameter is double the radius,

Substituting into our area formula we get:

Rearranging for

For circle A:

For circle B:

And no prizes for guessing that this evaluates to:

**So what do we notice?**

This is going to go into more detail than you need for your homework, although you may wish to read it; I personally find this stuff quite interesting.

Look at our answers.

In fact,

No wonder we often round it to

This decimal will repeat. So too will any fraction you can come up with. **irrational** number. Other irrational numbers include irrational square roots, such as **transcendental** number.

Both of these mean we can never actually describe pi accurately as a decimal. In fact, if we wanted to be accurate, we would leave the answers in terms on