How many integer values of x satisfy |x| < 3π?

2021 AMC 10B Spring Problem 1

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How many integer values of

x

satisfy

|x| < 3\pi?

9

10

18

19

20

Use

3\pi

as a little more than

9

Count the integers strictly between

-3\pi

and

3\pi

Every integer from

-9

9,

inclusive, works. This yields

9-(-9)+1 = 19

solutions.

Thus, the correct answer is D .