Finding the Fourth Proportional to 139.01, 208.31 and 57.83

Step by Step Solution

1. Step 1: Write the proportion equation
   139.01 : 208.31 = 57.83 : x
2. Step 2: Convert to fraction form
   139.01/208.31 = 57.83/x
3. Step 3: Cross multiply
   139.01x = 208.31 × 57.83
4. Step 4: Simplify right side
   139.01x = 12,046.28
5. Step 5: Solve for x
   x = 12,046.28/139.01
6. Step 6: Final answer
   x = 86.66