Hello, There are endless expressions. Since, you multiply this fraction by a costant k / k
If k = 2
Then,
(5/9) = ( 5/9) × ( k / k)
= (5/9) × ( 2/2)
= (5 × 2 / 9×2)
= 10 / 18
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The only restriction for k is zero and the infinite. Because there is no "0/0" and "infinito/ infinito" at math.
