Finding the Fourth Proportional to 71,843.20, 99,143.61 and 40,012.09

Step by Step Solution

1. Step 1: Write the proportion equation
   71,843.20 : 99,143.61 = 40,012.09 : x
2. Step 2: Convert to fraction form
   71,843.20/99,143.61 = 40,012.09/x
3. Step 3: Cross multiply
   71,843.20x = 99,143.61 × 40,012.09
4. Step 4: Simplify right side
   71,843.20x = 3,966,942,648.34
5. Step 5: Solve for x
   x = 3,966,942,648.34/71,843.20
6. Step 6: Final answer
   x = 55,216.68