Finding the Fourth Proportional to 10,399.48, 14,362.18 and 8,980.36

Step by Step Solution

1. Step 1: Write the proportion equation
   10,399.48 : 14,362.18 = 8,980.36 : x
2. Step 2: Convert to fraction form
   10,399.48/14,362.18 = 8,980.36/x
3. Step 3: Cross multiply
   10,399.48x = 14,362.18 × 8,980.36
4. Step 4: Simplify right side
   10,399.48x = 128,977,546.78
5. Step 5: Solve for x
   x = 128,977,546.78/10,399.48
6. Step 6: Final answer
   x = 12,402.31