To calculate the percentage change from 75 to 50, we need to follow the below steps:

Step 1: Calculate the difference between the two numbers. In this case, the difference is 75 - 50 = 25.

Step 2: Divide the difference by the original number (75) and multiply by 100 to get the percentage change. So, (25/75) x 100 = 33.33%.

Step 3: Since the output is negative, we can conclude that there is a decrease of 33.33% from 75 to 50.

Therefore, the percentage change from 75 to 50 is a decrease of 33.33%.