Finding the Fourth Proportional to 9,899.43, 13,661.29 and 5,423.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,899.43 : 13,661.29 = 5,423.60 : x
2. Step 2: Convert to fraction form
   9,899.43/13,661.29 = 5,423.60/x
3. Step 3: Cross multiply
   9,899.43x = 13,661.29 × 5,423.60
4. Step 4: Simplify right side
   9,899.43x = 74,093,304.14
5. Step 5: Solve for x
   x = 74,093,304.14/9,899.43
6. Step 6: Final answer
   x = 7,484.61