Question

a circle is enlarged. the original had a radius of 10 cm. if the new circle has a radius of 30 cm, how many times bigger is the new circumference than the original?

Answer 1

3 times bigger

Explanation:

`circumference \: of \: a \: circle \: has \: the \: formular \\ c = 2\pi \: r \\for \: the \: original \: circle \: c = 2 * 3.14 * 10 = 6.28 \\ = 63 \: approxiately \\ for \: the \: new \: circle \: c = 2 * 3.14 * 30 = 188.8 \\ = 188 \: approximately \\ them \: (188)/(63) =2.984 \\ = 3 \: approximately \\ therefore \: the \: bigger \: circumferene \: is \: 3 \: times \: the \: smaller \: circumference`