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If #pi# equals #22/7# and the radius of a circle is #1##3/4# in, what is the circumference?

Answer 1

Ella Armstrong

Approximately #11# in

Please note that #pi# is not equal to #22/7#

#22/7# is a rational number equal to #3.bar(142857)#

#pi# is an irrational number whose decimal expansion starts...

#3.141592653589793238462643383279502884...#

Using the approximation #pi ~~ 22/7# and the formula #c = 2pi r# we find:

#c = 2pi r ~~ 2 * 22/7 * 1 3/4 =2 * 22/7 * 7/4 = 44/4 = 11# in

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Answer 2

Sadie Allen

Using the formula for the circumference of a circle:

[ C = 2 \pi r ]

Substitute the given value of ( \pi = \frac{22}{7} ) and the radius ( r = \frac{13}{4} ):

[ C = 2 \times \frac{22}{7} \times \frac{13}{4} ]

[ C = \frac{44}{7} \times \frac{13}{4} ]

[ C = \frac{572}{28} ]

[ C = \frac{143}{7} ]

Therefore, the circumference of the circle is ( \frac{143}{7} ) inches.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.