Finding the Fourth Proportional to 85,776.48, 128,664.72 and 39,042.72

Step by Step Solution

1. Step 1: Write the proportion equation
   85,776.48 : 128,664.72 = 39,042.72 : x
2. Step 2: Convert to fraction form
   85,776.48/128,664.72 = 39,042.72/x
3. Step 3: Cross multiply
   85,776.48x = 128,664.72 × 39,042.72
4. Step 4: Simplify right side
   85,776.48x = 5,023,420,636.84
5. Step 5: Solve for x
   x = 5,023,420,636.84/85,776.48
6. Step 6: Final answer
   x = 58,564.08