Finding the Fourth Proportional to 105,542.37, 145,648.53 and 57,144.72

Step by Step Solution

1. Step 1: Write the proportion equation
   105,542.37 : 145,648.53 = 57,144.72 : x
2. Step 2: Convert to fraction form
   105,542.37/145,648.53 = 57,144.72/x
3. Step 3: Cross multiply
   105,542.37x = 145,648.53 × 57,144.72
4. Step 4: Simplify right side
   105,542.37x = 8,323,043,782.53
5. Step 5: Solve for x
   x = 8,323,043,782.53/105,542.37
6. Step 6: Final answer
   x = 78,859.74