Because 1 10=10 and 2 5=10
Answer
The fourth factor is 5
Explanation
It is given that there are only four factors. Three of them are 1, 2, 10
Here 10 is a factor, so we know that , if 10 is a factor of a number,
the we can write, 10 = 5 x 2, it implies that 5 and 2 are the factors of that number. Here 2 is given. Therefore the fourth factor is 5
The four factors are 1,2,5 and 10
The fourth factor is 5. When you multiply the factors 1, 2, and 5, you get the fourth factor of 10, which shows that all four factors are 1, 2, 5, and 10. Therefore, the answer to your question is 5.
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