Finding the Fourth Proportional to 20,978.82, 31,468.31 and 8,499.08

Step by Step Solution

1. Step 1: Write the proportion equation
   20,978.82 : 31,468.31 = 8,499.08 : x
2. Step 2: Convert to fraction form
   20,978.82/31,468.31 = 8,499.08/x
3. Step 3: Cross multiply
   20,978.82x = 31,468.31 × 8,499.08
4. Step 4: Simplify right side
   20,978.82x = 267,451,705.40
5. Step 5: Solve for x
   x = 267,451,705.40/20,978.82
6. Step 6: Final answer
   x = 12,748.65