Finding the Fourth Proportional to 102.82, 141.58 and 86.42

Step by Step Solution

1. Step 1: Write the proportion equation
   102.82 : 141.58 = 86.42 : x
2. Step 2: Convert to fraction form
   102.82/141.58 = 86.42/x
3. Step 3: Cross multiply
   102.82x = 141.58 × 86.42
4. Step 4: Simplify right side
   102.82x = 12,235.34
5. Step 5: Solve for x
   x = 12,235.34/102.82
6. Step 6: Final answer
   x = 119.00