Finding the Fourth Proportional to 12,891, 17,759.22 and 12,115.98

Step by Step Solution

1. Step 1: Write the proportion equation
   12,891 : 17,759.22 = 12,115.98 : x
2. Step 2: Convert to fraction form
   12,891/17,759.22 = 12,115.98/x
3. Step 3: Cross multiply
   12,891x = 17,759.22 × 12,115.98
4. Step 4: Simplify right side
   12,891x = 215,170,354.34
5. Step 5: Solve for x
   x = 215,170,354.34/12,891
6. Step 6: Final answer
   x = 16,691.52