Finding the Fourth Proportional to 10,387.31, 15,585.53 and 5,455.83

Step by Step Solution

1. Step 1: Write the proportion equation
   10,387.31 : 15,585.53 = 5,455.83 : x
2. Step 2: Convert to fraction form
   10,387.31/15,585.53 = 5,455.83/x
3. Step 3: Cross multiply
   10,387.31x = 15,585.53 × 5,455.83
4. Step 4: Simplify right side
   10,387.31x = 85,032,002.14
5. Step 5: Solve for x
   x = 85,032,002.14/10,387.31
6. Step 6: Final answer
   x = 8,186.14