Finding the Fourth Proportional to 102.71, 141.57 and 78.71

Step by Step Solution

1. Step 1: Write the proportion equation
   102.71 : 141.57 = 78.71 : x
2. Step 2: Convert to fraction form
   102.71/141.57 = 78.71/x
3. Step 3: Cross multiply
   102.71x = 141.57 × 78.71
4. Step 4: Simplify right side
   102.71x = 11,142.27
5. Step 5: Solve for x
   x = 11,142.27/102.71
6. Step 6: Final answer
   x = 108.48