Finding the Fourth Proportional to 72.83, 109.31 and 57.57

Step by Step Solution

1. Step 1: Write the proportion equation
   72.83 : 109.31 = 57.57 : x
2. Step 2: Convert to fraction form
   72.83/109.31 = 57.57/x
3. Step 3: Cross multiply
   72.83x = 109.31 × 57.57
4. Step 4: Simplify right side
   72.83x = 6,292.69
5. Step 5: Solve for x
   x = 6,292.69/72.83
6. Step 6: Final answer
   x = 86.41