Finding the Fourth Proportional to 102.42, 141.24 and 71.28

Step by Step Solution

1. Step 1: Write the proportion equation
   102.42 : 141.24 = 71.28 : x
2. Step 2: Convert to fraction form
   102.42/141.24 = 71.28/x
3. Step 3: Cross multiply
   102.42x = 141.24 × 71.28
4. Step 4: Simplify right side
   102.42x = 10,067.59
5. Step 5: Solve for x
   x = 10,067.59/102.42
6. Step 6: Final answer
   x = 98.30