Re: The number x belongs to a set of prime numbers less than 10 and the nu
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09 Dec 2024, 10:55
We know that the number x belongs to a set of prime numbers less than 10 which implies that x can take any value out of $(2,3,5,7)$ and the number $y$ belongs to a set of prime numbers greater than 10 , so $y$ can take any value out of $(11,13,17,19&$ so on)
It is clear that the value of $y$ must be an odd number whereas $x$ can be either even or odd.
If we consider $x=$evenprime$=2&y$ any odd prime number, we get column A quantity as $(−1)(x+y)=(−1)(even+odd )=(−1)(odd )=−1&$ column $B$ quantity comes out to be $(−1)(xy)=(−1)(cven×odd)=(−1)(cven)=1$ which implies column B has higher quantity.
Next if we take $x$ as well as $y$ as odd prime numbers we get $(−1)(x+y)=(−1)(odd + odd )=(−1)(even )=1&(−1)(xy)=(−1)(odd × odd )=(−1)(odd )=−1$ which gives column A higher than column B
As a unique relation cannot be formed between column A \& column B quantities, the answer is (D).