Finding the Fourth Proportional to 57,558.72, 78,912.96 and 56,508.96

Step by Step Solution

1. Step 1: Write the proportion equation
   57,558.72 : 78,912.96 = 56,508.96 : x
2. Step 2: Convert to fraction form
   57,558.72/78,912.96 = 56,508.96/x
3. Step 3: Cross multiply
   57,558.72x = 78,912.96 × 56,508.96
4. Step 4: Simplify right side
   57,558.72x = 4,459,289,300.12
5. Step 5: Solve for x
   x = 4,459,289,300.12/57,558.72
6. Step 6: Final answer
   x = 77,473.74