Question

In order to increase the circumference of a circle from 12π cm to 18π cm, by how much must the diameter increase?

Answer 1

Answer:

Step-by-step explanation:

It's actually 6 cm. This is because the diameter of the smaller circle is 12pi/pi which is 12, and the diameter of the bigger one is 18pi/pi which is 18. 12 + 6 = 18, so the diameter increases by 6.

Answer 2

Answer: The increase in the diameter is 6 cm.

Step-by-step explanation:

The circumference of a circle with diameter 'd' is given by :

Circumference=$\pi d$

Given: The circumference is increased from $12\pi\ cm\ to\ 18\pi\ cm$

It implies the increase in the circumference=$\pi d_2-\pi d_1=18\pi-12\pi$, where $d_1$ is the previous diameter and $d_2$

is the new diameter.

$\Rightarrow\pi(d_2-d_1)=\pi(18-12)\\\Rightarrow(d_2-d_1)=6$

Hence, the increase in the diameter= 6 cm