Finding the Fourth Proportional to 9,900.87, 13,662.81 and 5,424.54

Step by Step Solution

1. Step 1: Write the proportion equation
   9,900.87 : 13,662.81 = 5,424.54 : x
2. Step 2: Convert to fraction form
   9,900.87/13,662.81 = 5,424.54/x
3. Step 3: Cross multiply
   9,900.87x = 13,662.81 × 5,424.54
4. Step 4: Simplify right side
   9,900.87x = 74,114,459.36
5. Step 5: Solve for x
   x = 74,114,459.36/9,900.87
6. Step 6: Final answer
   x = 7,485.65