Finding the Fourth Proportional to 105,469.43, 145,540.40 and 57,721.82

Step by Step Solution

1. Step 1: Write the proportion equation
   105,469.43 : 145,540.40 = 57,721.82 : x
2. Step 2: Convert to fraction form
   105,469.43/145,540.40 = 57,721.82/x
3. Step 3: Cross multiply
   105,469.43x = 145,540.40 × 57,721.82
4. Step 4: Simplify right side
   105,469.43x = 8,400,855,755.22
5. Step 5: Solve for x
   x = 8,400,855,755.22/105,469.43
6. Step 6: Final answer
   x = 79,652.05