To find the percentage change from 40 to 60, we need to first calculate the difference between the two numbers.

Step 1: Difference = Final Value - Initial Value

Difference = 60 - 40

Difference = 20

Step 2: Next, we need to find the absolute value of the difference. This is because percentage change is always calculated as a positive value.

Absolute Difference = |Difference|

Absolute Difference = |20|

Absolute Difference = 20

Step 3: Now, we can calculate the percentage change using the formula:

Percentage Change = (Absolute Difference / Initial Value) x 100

Percentage Change = (20 / 40) x 100

Percentage Change = 50%

Therefore, the percentage change from 40 to 60 is 50%. This means that there was an increase of 50% from 40 to 60.