Finding the Fourth Proportional to 9,411.49, 12,986.37 and 5,431.86

Step by Step Solution

1. Step 1: Write the proportion equation
   9,411.49 : 12,986.37 = 5,431.86 : x
2. Step 2: Convert to fraction form
   9,411.49/12,986.37 = 5,431.86/x
3. Step 3: Cross multiply
   9,411.49x = 12,986.37 × 5,431.86
4. Step 4: Simplify right side
   9,411.49x = 70,540,092.40
5. Step 5: Solve for x
   x = 70,540,092.40/9,411.49
6. Step 6: Final answer
   x = 7,495.11