Examples with solutions for Circumference: Calculating parts of the circle

Exercise #1

Jacob cut a slice that was 16 \frac{1}{6} of a whole cake.

What is the circumference of the cake now given that its radius is 20 cm?

202020

Video Solution

Answer

3313π+40 33\frac{1}{3}\pi+40 cm

Exercise #2

Given the circle in the figure

Radius of the circle 5a+8 5a+8 cm

The sector marked in blue is displayed by an angle of size 24 degrees.

What is the circumference of the section marked in blue?

242424

Video Solution

Answer

10a+16+(23a+1115)π 10a+16+(\frac{2}{3}a+1\frac{1}{15})\pi cm

Exercise #3

Given the circle in the figure,

and above it there are two arches marked in blue.

The radius is equal to 5.

What is the sum of the lengths of the arcs?

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Video Solution

Answer

2.5π 2.5\pi cm

Exercise #4

The radius or the circle shown below is 4 cm.

What is the circumference of the shape marked in blue?

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Video Solution

Answer

53π+24 \frac{5}{3}\pi+24 cm

Exercise #5

Look at the circle in the figure.

What is the perimeter of the segment highlighted in blue?

151515131313

Video Solution

Answer

39.12 cm

Exercise #6

In the drawing, a rectangle and a circle whose center is the corner of the rectangle.

Given R=4

What is the length of the highlighted part in the drawing?

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Video Solution

Answer

3245π \frac{32}{45}\pi