Finding the Fourth Proportional to 102.78, 141.82 and 59.12

Step by Step Solution

1. Step 1: Write the proportion equation
   102.78 : 141.82 = 59.12 : x
2. Step 2: Convert to fraction form
   102.78/141.82 = 59.12/x
3. Step 3: Cross multiply
   102.78x = 141.82 × 59.12
4. Step 4: Simplify right side
   102.78x = 8,384.40
5. Step 5: Solve for x
   x = 8,384.40/102.78
6. Step 6: Final answer
   x = 81.58