Finding the Fourth Proportional to 12,891.78, 17,789.76 and 7,585.47

Step by Step Solution

1. Step 1: Write the proportion equation
   12,891.78 : 17,789.76 = 7,585.47 : x
2. Step 2: Convert to fraction form
   12,891.78/17,789.76 = 7,585.47/x
3. Step 3: Cross multiply
   12,891.78x = 17,789.76 × 7,585.47
4. Step 4: Simplify right side
   12,891.78x = 134,943,690.79
5. Step 5: Solve for x
   x = 134,943,690.79/12,891.78
6. Step 6: Final answer
   x = 10,467.42