Lesson 7: Practice Problems

Problem 1

The -axis of each graph has the diameter of a circle in meters. Label the -axis on each graph with the appropriate measurement of a circle: radius (m), circumference (m), or area (m²).

3 graphs with diameter(m) on the x axis. The first graph is a curved line from 0. The second is a straight line increasing slowly from 0 and the third is a steeper straight line.

Problem 2

Circle has area 500 in. The diameter of circle is three times the diameter of circle . Estimate the area of circle .

Problem 3 From Unit 3 Lesson 5

Lin’s bike travels 100 meters when her wheels rotate 55 times. What is the circumference of her wheels?

Problem 4 From Unit 3 Lesson 3

Priya drew a circle whose circumference is 25 cm. Clare drew a circle whose diameter is 3 times the diameter of Priya’s circle. What is the circumference of Clare’s circle?

Problem 5

  1. Here is a picture of two squares and a circle. Use the picture to explain why the area of this circle is more than 2 square units but less than 4 square units.

    Two squares and circle on a grid of 4 units by four units. In the center of the grid is a square that measures two units high by two units wide. Within the square is a circle, with a diameter of 2 units. Within the circle is another square, rotated so that the each of the four vertices of the square meet with a point of the circle and the midpoint of the larger square.

  2. Here is another picture of two squares and a circle. Use the picture to explain why the area of this circle is more than 18 square units and less than 36 square units.

    A square with side lengths of 6. A circle is inside it touching all the edges. A square is inside the circle turned so that its vertices touch the circle and the larger square.

Problem 6 From Unit 3 Lesson 3

Point is the center of the circle, and the length of is 15 centimeters. Find the circumference of this circle.

A circle with a center A. A diameter line CD measures 15 cm. There are radius lines from A to B, E, and G