Finding the Fourth Proportional to 20,978.42, 31,467.71 and 8,498.68

Step by Step Solution

1. Step 1: Write the proportion equation
   20,978.42 : 31,467.71 = 8,498.68 : x
2. Step 2: Convert to fraction form
   20,978.42/31,467.71 = 8,498.68/x
3. Step 3: Cross multiply
   20,978.42x = 31,467.71 × 8,498.68
4. Step 4: Simplify right side
   20,978.42x = 267,433,955.13
5. Step 5: Solve for x
   x = 267,433,955.13/20,978.42
6. Step 6: Final answer
   x = 12,748.05