Finding the Fourth Proportional to 11,424.86, 15,762.72 and 6,388.40

Step by Step Solution

1. Step 1: Write the proportion equation
   11,424.86 : 15,762.72 = 6,388.40 : x
2. Step 2: Convert to fraction form
   11,424.86/15,762.72 = 6,388.40/x
3. Step 3: Cross multiply
   11,424.86x = 15,762.72 × 6,388.40
4. Step 4: Simplify right side
   11,424.86x = 100,698,560.45
5. Step 5: Solve for x
   x = 100,698,560.45/11,424.86
6. Step 6: Final answer
   x = 8,813.99