Understanding Proportion Method for Circle Area

The video tutorial explains how to find the area of a circle using the proportion method. It begins by introducing the method and setting up a proportion using the sector area and arc measure. The tutorial then demonstrates solving the proportion to find the circle's area, emphasizing the ease of using cross products. The video concludes by highlighting the preference for the proportion method over the formula method.

What is the initial step in using the proportion method to find the area of a circle?

• Use the formula for the area of a circle

• Calculate the circumference of the circle

• Set the sector area equal to the arc measure over 360

• Find the radius of the circle

What is the measure of the arc used in the proportion method in this lesson?

• 150 degrees

• 180 degrees

• 90 degrees

• 360 degrees

How is the proportion simplified before performing cross multiplication?

• By dividing both terms by 10 and then by 3

• By adding the numerators

• By multiplying both terms by 2

• By subtracting the denominators

Tags

CCSS.4.MD.A.2

What is the result of the cross multiplication in this lesson?

• 5x = 1140

• 5x = 228

• x = 360

• 12x = 95

Tags

CCSS.7.G.B.4

What is the final area of the circle calculated using the proportion method?

• 360 cm

• 228 cm

• 150 cm

• 95 cm

Tags

CCSS.7.G.A.1

Why does the teacher prefer the proportion method over the formula method?

• It is faster to compute

• It is easier to understand

• It is more accurate

• It requires less data

Tags

CCSS.7.G.A.1