Finding the Fourth Proportional to 12,540.89, 17,306.53 and 8,561.90

Step by Step Solution

1. Step 1: Write the proportion equation
   12,540.89 : 17,306.53 = 8,561.90 : x
2. Step 2: Convert to fraction form
   12,540.89/17,306.53 = 8,561.90/x
3. Step 3: Cross multiply
   12,540.89x = 17,306.53 × 8,561.90
4. Step 4: Simplify right side
   12,540.89x = 148,176,801.07
5. Step 5: Solve for x
   x = 148,176,801.07/12,540.89
6. Step 6: Final answer
   x = 11,815.49