Finding the Fourth Proportional to 102.72, 141.57 and 75.05

Step by Step Solution

1. Step 1: Write the proportion equation
   102.72 : 141.57 = 75.05 : x
2. Step 2: Convert to fraction form
   102.72/141.57 = 75.05/x
3. Step 3: Cross multiply
   102.72x = 141.57 × 75.05
4. Step 4: Simplify right side
   102.72x = 10,624.12
5. Step 5: Solve for x
   x = 10,624.12/102.72
6. Step 6: Final answer
   x = 103.43