Finding the Fourth Proportional to 9,899.38, 13,661.15 and 5,423.15

Step by Step Solution

1. Step 1: Write the proportion equation
   9,899.38 : 13,661.15 = 5,423.15 : x
2. Step 2: Convert to fraction form
   9,899.38/13,661.15 = 5,423.15/x
3. Step 3: Cross multiply
   9,899.38x = 13,661.15 × 5,423.15
4. Step 4: Simplify right side
   9,899.38x = 74,086,465.62
5. Step 5: Solve for x
   x = 74,086,465.62/9,899.38
6. Step 6: Final answer
   x = 7,483.95