Finding the Fourth Proportional to 105,443.20, 145,514.88 and 57,698.56

Step by Step Solution

1. Step 1: Write the proportion equation
   105,443.20 : 145,514.88 = 57,698.56 : x
2. Step 2: Convert to fraction form
   105,443.20/145,514.88 = 57,698.56/x
3. Step 3: Cross multiply
   105,443.20x = 145,514.88 × 57,698.56
4. Step 4: Simplify right side
   105,443.20x = 8,395,999,034.57
5. Step 5: Solve for x
   x = 8,395,999,034.57/105,443.20
6. Step 6: Final answer
   x = 79,625.80