Finding the Fourth Proportional to 28,105.54, 42,124.47 and 10,321.90

Step by Step Solution

1. Step 1: Write the proportion equation
   28,105.54 : 42,124.47 = 10,321.90 : x
2. Step 2: Convert to fraction form
   28,105.54/42,124.47 = 10,321.90/x
3. Step 3: Cross multiply
   28,105.54x = 42,124.47 × 10,321.90
4. Step 4: Simplify right side
   28,105.54x = 434,804,566.89
5. Step 5: Solve for x
   x = 434,804,566.89/28,105.54
6. Step 6: Final answer
   x = 15,470.42