Finding the Fourth Proportional to 85,947.56, 128,899.02 and 57,851.72

Step by Step Solution

1. Step 1: Write the proportion equation
   85,947.56 : 128,899.02 = 57,851.72 : x
2. Step 2: Convert to fraction form
   85,947.56/128,899.02 = 57,851.72/x
3. Step 3: Cross multiply
   85,947.56x = 128,899.02 × 57,851.72
4. Step 4: Simplify right side
   85,947.56x = 7,457,030,013.31
5. Step 5: Solve for x
   x = 7,457,030,013.31/85,947.56
6. Step 6: Final answer
   x = 86,762.56