Is 121 a composite number?
Understand the Problem
The question is asking if the number 121 is a composite number. A composite number is defined as a positive integer that has at least one positive divisor other than one or itself. To determine if 121 is composite, we need to check its factors.
Answer
Yes, 121 is a composite number.
Answer for screen readers
Yes, 121 is a composite number.
Steps to Solve
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Identifying divisors To check if 121 is a composite number, we will first look for its divisors. A positive integer $n$ is composite if it can be divided evenly by any integer $p$ where $1 < p < n$.
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Calculating divisors We can check the divisors starting from $2$ up to $\sqrt{121}$. The square root of $121$ is $11$ since $11 \times 11 = 121$.
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Checking divisibility We will check if $121$ is divisible by the integers $2, 3, 4, \ldots, 11$. We find that:
- $121 \div 2$ is not an integer.
- $121 \div 3$ is not an integer.
- $121 \div 4$ is not an integer.
- $121 \div 5$ is not an integer.
- $121 \div 6$ is not an integer.
- $121 \div 7$ is not an integer.
- $121 \div 8$ is not an integer.
- $121 \div 9$ is not an integer.
- $121 \div 10$ is not an integer.
- $121 \div 11 = 11$ (which is an integer).
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Conclusion Since $121$ can be divided by $11$, we find that $121$ has divisors other than $1$ and itself. Therefore, it is a composite number.
Yes, 121 is a composite number.
More Information
A composite number has more factors than just $1$ and itself. In the case of $121$, it is equal to $11 \times 11$, so it has divisors that confirm its composite nature.
Tips
One common mistake is confusing composite numbers with prime numbers. Remember, a prime number has only two distinct positive divisors: $1$ and itself.
