Finding the Fourth Proportional to 28,155.80, 42,227.39 and 8,431.83

Step by Step Solution

1. Step 1: Write the proportion equation
   28,155.80 : 42,227.39 = 8,431.83 : x
2. Step 2: Convert to fraction form
   28,155.80/42,227.39 = 8,431.83/x
3. Step 3: Cross multiply
   28,155.80x = 42,227.39 × 8,431.83
4. Step 4: Simplify right side
   28,155.80x = 356,054,194.90
5. Step 5: Solve for x
   x = 356,054,194.90/28,155.80
6. Step 6: Final answer
   x = 12,645.85