Finding the Fourth Proportional to 103,510.20, 155,067.31 and 86,750.43

Step by Step Solution

1. Step 1: Write the proportion equation
   103,510.20 : 155,067.31 = 86,750.43 : x
2. Step 2: Convert to fraction form
   103,510.20/155,067.31 = 86,750.43/x
3. Step 3: Cross multiply
   103,510.20x = 155,067.31 × 86,750.43
4. Step 4: Simplify right side
   103,510.20x = 13,452,155,348.38
5. Step 5: Solve for x
   x = 13,452,155,348.38/103,510.20
6. Step 6: Final answer
   x = 129,959.70