Competition problem — Algebra — Maths Olympiad Prep

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Algebra Difficulty 1.9 Junior Find the answer

How many integer values of $x$ satisfy $|x|<3\pi$ ?
$\textbf{(A)} ~9$ $\textbf{(B)} ~10$ $\textbf{(C)} ~18$ $\textbf{(D)} ~19$ $\textbf{(E)} ~20$

Your answer

Multiple choice: answer with the letter of the option you want.

Solution

Since $3\pi\approx9.42$ , we multiply $9$ by $2$ for the integers from $1$ to $9$ and the integers from $-1$ to $-9$ and add $1$ to account for $0$ to get $\boxed{\textbf{(D)} ~19}$ .
~smarty101 and edited by Tony_Li2007 and sl_hc

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.