The picture shows a circle divided into 8 equal wedges which are rearranged.
The radius of a circle is r and its circumference is 2πr. How does the picture help to explain why the area of the circle is πr²?

The perimeter of a stage is 116 feet. it is 17 feet wide. how long is it?

At the county fair, the baxter family bought 6 hot dogs and 4 juice drinks for $12.90. the farley family bought 3 hot dogs and 4 juice drinks for $8.55. find the price of a hot dog and the price of a juice drink.

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?