Finding the Fourth Proportional to 105,268.43, 145,268.69 and 57,520.76

Step by Step Solution

1. Step 1: Write the proportion equation
   105,268.43 : 145,268.69 = 57,520.76 : x
2. Step 2: Convert to fraction form
   105,268.43/145,268.69 = 57,520.76/x
3. Step 3: Cross multiply
   105,268.43x = 145,268.69 × 57,520.76
4. Step 4: Simplify right side
   105,268.43x = 8,355,964,439.06
5. Step 5: Solve for x
   x = 8,355,964,439.06/105,268.43
6. Step 6: Final answer
   x = 79,377.69