Finding the Fourth Proportional to 86.18, 129.25 and 42.83

Step by Step Solution

1. Step 1: Write the proportion equation
   86.18 : 129.25 = 42.83 : x
2. Step 2: Convert to fraction form
   86.18/129.25 = 42.83/x
3. Step 3: Cross multiply
   86.18x = 129.25 × 42.83
4. Step 4: Simplify right side
   86.18x = 5,535.18
5. Step 5: Solve for x
   x = 5,535.18/86.18
6. Step 6: Final answer
   x = 64.23