Find the circumference of a circle with a radius of 9.7 millimeters. Use [tex]$\pi=3.14$[/tex]. Round your answer to the nearest hundredth, if necessary.
Answer (1)
Use the formula for the circumference of a circle: C = 2 π r .
Substitute the given values: C = 2 × 3.14 × 9.7 = 60.916 .
Round the result to the nearest hundredth: C ≈ 60.92 .
The circumference of the circle is: 60.92 mm .
Explanation
Problem Analysis and Given Data We are given a circle with a radius of 9.7 millimeters, and we need to find its circumference using the value of π = 3.14 . The formula for the circumference of a circle is C = 2 π r , where C is the circumference and r is the radius.
Substitute Values into Formula Now, we substitute the given values into the formula: C = 2 × 3.14 × 9.7 C = 6.28 × 9.7 C = 60.916
Round to Nearest Hundredth We need to round the result to the nearest hundredth. The result of the calculation is 60.916. The digit in the thousandths place is 6, which is greater than or equal to 5, so we round up the hundredths place. C ≈ 60.92
Final Answer Therefore, the circumference of the circle, rounded to the nearest hundredth, is 60.92 millimeters.
Examples
Imagine you are designing a circular garden bed and need to determine the amount of edging material to purchase. Knowing the radius of the garden bed allows you to calculate the circumference, which directly corresponds to the length of edging needed. For instance, if your garden bed has a radius of 9.7 meters, you would calculate the circumference as C = 2 π r = 2 × 3.14 × 9.7 ≈ 60.92 meters. This ensures you buy the correct amount of edging to complete your garden design.
