Finding the Fourth Proportional to 15,563.86, 21,478.27 and 8,490.42

Step by Step Solution

1. Step 1: Write the proportion equation
   15,563.86 : 21,478.27 = 8,490.42 : x
2. Step 2: Convert to fraction form
   15,563.86/21,478.27 = 8,490.42/x
3. Step 3: Cross multiply
   15,563.86x = 21,478.27 × 8,490.42
4. Step 4: Simplify right side
   15,563.86x = 182,359,533.17
5. Step 5: Solve for x
   x = 182,359,533.17/15,563.86
6. Step 6: Final answer
   x = 11,716.86