Original Length of the Ribbon:
The original length of the ribbon is given as 30 cm.

Ratio of Reduction:
The ribbon is reduced in the ratio 5:3.

Interpreting the Ratio:
In the given ratio, the first number (5) represents the original length of the ribbon, and the second number (3) represents the reduced length of the ribbon.

Calculating the Reduced Length:
To find the reduced length of the ribbon, we need to divide the original length by the sum of the two ratio numbers and then multiply it by the second ratio number.

Let's calculate it step by step:

Step 1: Find the sum of the ratio numbers: 5 + 3 = 8
Step 2: Divide the original length by the sum of the ratio numbers: 30 / 8 = 3.75
Step 3: Multiply the result by the second ratio number: 3.75 * 3 = 11.25

So, the reduced length of the ribbon is 11.25 cm.

Explanation:
The original length of the ribbon is 30 cm. When it is reduced in the ratio 5:3, the reduced length is calculated using the formula mentioned above. This formula ensures that the reduced length is proportionate to the original length based on the given ratio. In this case, the reduced length is found to be 11.25 cm.

Summary:
- The original length of the ribbon is 30 cm.
- The ribbon is reduced in the ratio 5:3.
- The reduced length of the ribbon is calculated using the formula: original length / (sum of ratio numbers) * second ratio number.
- After calculating, the reduced length of the ribbon is found to be 11.25 cm.