75/2 x 1/100 = 3/8

Please show how to came up with the answer?

You need to find a factors that appear in both the numerator and the denominator which you can cancel. With this problem the first fact I see is that 75 = 3 x 25. The second fraction has 100 is the denominator and 100 = 4 x 25. Thus

Multiplying fractions involves multiplying the numerators and denominators, hence

Now you can cancel the 25's and the product or 75/2 and 1/100 is