Finding the Fourth Proportional to 105,406.48, 145,462.17 and 57,658.80

Step by Step Solution

1. Step 1: Write the proportion equation
   105,406.48 : 145,462.17 = 57,658.80 : x
2. Step 2: Convert to fraction form
   105,406.48/145,462.17 = 57,658.80/x
3. Step 3: Cross multiply
   105,406.48x = 145,462.17 × 57,658.80
4. Step 4: Simplify right side
   105,406.48x = 8,387,174,167.60
5. Step 5: Solve for x
   x = 8,387,174,167.60/105,406.48
6. Step 6: Final answer
   x = 79,569.82