To find the percentage change of the first quantity (72 units) with reference to the second quantity (60 units), you can follow these steps:
1. Calculate the difference between the two quantities: Subtract the second quantity from the first quantity. In this case, 72 - 60 = 12.
2. Divide the difference by the second quantity: Divide the difference obtained in the previous step by the second quantity (60). In this case, 12 ÷ 60 = 0.2.
3. Multiply the result by 100: Multiply the quotient from step 2 by 100 to convert it to a percentage. In this case, 0.2 x 100 = 20.
4. Interpret the result: The resulting percentage (20%) represents the percentage change of the first quantity (72 units) with reference to the second quantity (60 units). In this case, there is a 20% increase in the first quantity compared to the second quantity.
Therefore, the percentage change of the first quantity (72 units) with reference to the second quantity (60 units) is 20%.