Finding the Fourth Proportional to 21,174.76, 31,734.43 and 8,680.15

Step by Step Solution

1. Step 1: Write the proportion equation
   21,174.76 : 31,734.43 = 8,680.15 : x
2. Step 2: Convert to fraction form
   21,174.76/31,734.43 = 8,680.15/x
3. Step 3: Cross multiply
   21,174.76x = 31,734.43 × 8,680.15
4. Step 4: Simplify right side
   21,174.76x = 275,459,612.56
5. Step 5: Solve for x
   x = 275,459,612.56/21,174.76
6. Step 6: Final answer
   x = 13,008.87