Congruence and Similarity of Circles
Interactive practice questions
We want to compare the circumference and area of two circles: circle A has radius $5$5 units and circle B has radius $40$40 units.
What is the circumference of circle A? Give your answer as an exact value.
What is the circumference of circle B? Give your answer as an exact value.
What is the area of circle A? Give your answer as an exact value.
What is the area of circle B? Give your answer as an exact value.
By what factor is the radius of circle A enlarged to give the radius of circle B?
By what factor is the circumference of circle A enlarged to give the circumference of circle B?
By what factor is the area of circle A enlarged to give the area of circle B?
A circle with a radius of $2$2 units is enlarged by a factor of $7$7.
Circle A has a perimeter measuring $10\pi$10π cm, while circle B has a radius measuring $10$10 cm.
The ratio of the circumference of circle A to the circumference of circle B is $\frac{4}{3}$43.