Question
Explain why $3 \times 5 \times 7 + 7$ is a composite number.
✓
Answer
We have, $3 \times 5 \times 7 + 7 = 105 + 7 = 112$
Now, $112 = 2 \times 2 \times 2 \times 2 \times 7 = 2^4 \times 7$
So, it is the product of prime factors $2$ and $7$. i.e., it has more than two factors.
Hence, it is a composite number.
Now, $112 = 2 \times 2 \times 2 \times 2 \times 7 = 2^4 \times 7$
So, it is the product of prime factors $2$ and $7$. i.e., it has more than two factors.
Hence, it is a composite number.
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