Finding the Fourth Proportional to 21,245.98, 31,872.78 and 8,759.05

Step by Step Solution

1. Step 1: Write the proportion equation
   21,245.98 : 31,872.78 = 8,759.05 : x
2. Step 2: Convert to fraction form
   21,245.98/31,872.78 = 8,759.05/x
3. Step 3: Cross multiply
   21,245.98x = 31,872.78 × 8,759.05
4. Step 4: Simplify right side
   21,245.98x = 279,175,273.66
5. Step 5: Solve for x
   x = 279,175,273.66/21,245.98
6. Step 6: Final answer
   x = 13,140.15