Find the value of \( (1-\frac{1}{3})(1-\frac{1}{4})(1-\frac{1}{5})\ldots(1-\frac{1}{100}) \)

Arun’s present age in years is 40% of Barun’s. In another few years, Arun’s age will be half of Barun’s. By what percentage will Barun’s age increase during this period?