Finding the Fourth Proportional to 105,145.80, 145,103.28 and 57,401.16

Step by Step Solution

1. Step 1: Write the proportion equation
   105,145.80 : 145,103.28 = 57,401.16 : x
2. Step 2: Convert to fraction form
   105,145.80/145,103.28 = 57,401.16/x
3. Step 3: Cross multiply
   105,145.80x = 145,103.28 × 57,401.16
4. Step 4: Simplify right side
   105,145.80x = 8,329,096,591.80
5. Step 5: Solve for x
   x = 8,329,096,591.80/105,145.80
6. Step 6: Final answer
   x = 79,214.73