Finding the Fourth Proportional to 105,057.86, 144,979.83 and 57,311.39

Step by Step Solution

1. Step 1: Write the proportion equation
   105,057.86 : 144,979.83 = 57,311.39 : x
2. Step 2: Convert to fraction form
   105,057.86/144,979.83 = 57,311.39/x
3. Step 3: Cross multiply
   105,057.86x = 144,979.83 × 57,311.39
4. Step 4: Simplify right side
   105,057.86x = 8,308,995,941.71
5. Step 5: Solve for x
   x = 8,308,995,941.71/105,057.86
6. Step 6: Final answer
   x = 79,089.72