Finding the Fourth Proportional to 86.17, 129.29 and 40.52

Step by Step Solution

1. Step 1: Write the proportion equation
   86.17 : 129.29 = 40.52 : x
2. Step 2: Convert to fraction form
   86.17/129.29 = 40.52/x
3. Step 3: Cross multiply
   86.17x = 129.29 × 40.52
4. Step 4: Simplify right side
   86.17x = 5,238.83
5. Step 5: Solve for x
   x = 5,238.83/86.17
6. Step 6: Final answer
   x = 60.80