The mean of 5 observations is 25. When a constant ‘x’ is added to each observation, the mean becomes 30. Find the value of x.

Sure, here is the step by step solution:

Step 1: The mean of 5 observations is 25. This means the total sum of these 5 observations is 5 * 25 = 125.

Step 2: When a constant ‘x’ is added to each observation, the mean becomes 30. This means the total sum of these 5 observations now is 5 * 30 = 150.

Step 3: The difference between the new sum (150) and the old sum (125) is the total amount added to the observations, which is 150 - 125 = 25.

Step 4: Since this total amount (25) was the result of adding ‘x’ to each of the 5 observations, we can find ‘x’ by dividing this total amount by the number of observations. So, x = 25 / 5 = 5.

Therefore, the value of x is 5.