Finding the Fourth Proportional to 20,670.90, 31,006.56 and 8,193.94

Step by Step Solution

1. Step 1: Write the proportion equation
   20,670.90 : 31,006.56 = 8,193.94 : x
2. Step 2: Convert to fraction form
   20,670.90/31,006.56 = 8,193.94/x
3. Step 3: Cross multiply
   20,670.90x = 31,006.56 × 8,193.94
4. Step 4: Simplify right side
   20,670.90x = 254,065,892.25
5. Step 5: Solve for x
   x = 254,065,892.25/20,670.90
6. Step 6: Final answer
   x = 12,290.99