2. A natural number is multiplied by two adjacent odd numbers respectively, and the difference between the two products is 100. What is this number?
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【Analysis】Assume this natural number is $\mathrm{a}$, and the two consecutive odd numbers are $\mathrm{x},(\mathrm{x}+2)$, according to the problem: $a(x+2)-a x=100$, so, $a x+2 a-a x=100,2 a=100, a=50$. That is, this number is 50.