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In a circle, the circumference and diameter vary directly. How do you find the diameter of a circle with a circumference of 154 if you know that in a second circle the diameter is 14 when the circumference is 44?

Answer 1

Eli Assouline

#D = 49#

#C = kD#

#C_1 = 154 = kD_1#

#C_2 = 44 = k(14)#

#=> k = 44/14 = 22/7#

#C_1 = 154 = 22/7D_1#

#D_1 = 154*7/22#

#D_1 = 49#

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Answer 2

Eva Abramson

You can use the formula for the circumference of a circle: ( C = \pi \times d ), where ( C ) is the circumference and ( d ) is the diameter. Rearranging the formula to solve for ( d ), you get ( d = \frac{C}{\pi} ). For the first circle with a circumference of 154, the diameter would be ( d = \frac{154}{\pi} ). For the second circle with a circumference of 44, the diameter would be ( d = \frac{44}{\pi} ).

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Answer from HIX Tutor

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