Finding the Fourth Proportional to 9,411.62, 12,987.31 and 5,161.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,411.62 : 12,987.31 = 5,161.98 : x
2. Step 2: Convert to fraction form
   9,411.62/12,987.31 = 5,161.98/x
3. Step 3: Cross multiply
   9,411.62x = 12,987.31 × 5,161.98
4. Step 4: Simplify right side
   9,411.62x = 67,040,234.47
5. Step 5: Solve for x
   x = 67,040,234.47/9,411.62
6. Step 6: Final answer
   x = 7,123.13