Given that k@ is defined as the product of all the fractions of the form 1/S, where S is a positive integer not greater than k and we need to find the value of 5@/4@

Lets start by finding the value of 5@

5@ = the product of all the fractions of the form 1/S, where S is a positive integer not greater than 5. => 1 ≤ S ≤ 5
=> 5@ = \(\frac{1}{1} * \frac{1}{2} * \frac{1}{3} * \frac{1}{4} * \frac{1}{5}\)

Similarly, 4@ = \(\frac{1}{1} * \frac{1}{2} * \frac{1}{3} * \frac{1}{4}\)

=> 5@/4@ = (\(\frac{1}{1} * \frac{1}{2} * \frac{1}{3} * \frac{1}{4} * \frac{1}{5}\)) / (\(\frac{1}{1} * \frac{1}{2} * \frac{1}{3} * \frac{1}{4}\))

All terms will cancel out except \(\frac{1}{5}\)

So, Answer will be A
Hope it helps!

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