Finding the Fourth Proportional to 9,899.93, 13,661.98 and 5,424.09

Step by Step Solution

1. Step 1: Write the proportion equation
   9,899.93 : 13,661.98 = 5,424.09 : x
2. Step 2: Convert to fraction form
   9,899.93/13,661.98 = 5,424.09/x
3. Step 3: Cross multiply
   9,899.93x = 13,661.98 × 5,424.09
4. Step 4: Simplify right side
   9,899.93x = 74,103,809.10
5. Step 5: Solve for x
   x = 74,103,809.10/9,899.93
6. Step 6: Final answer
   x = 7,485.29