Finding the Fourth Proportional to 57,518.88, 86,328.17 and 57,385.89

Step by Step Solution

1. Step 1: Write the proportion equation
   57,518.88 : 86,328.17 = 57,385.89 : x
2. Step 2: Convert to fraction form
   57,518.88/86,328.17 = 57,385.89/x
3. Step 3: Cross multiply
   57,518.88x = 86,328.17 × 57,385.89
4. Step 4: Simplify right side
   57,518.88x = 4,954,018,580.59
5. Step 5: Solve for x
   x = 4,954,018,580.59/57,518.88
6. Step 6: Final answer
   x = 86,128.56