Finding the Fourth Proportional to 10,939.90, 16,410.54 and 7,428.42

Step by Step Solution

1. Step 1: Write the proportion equation
   10,939.90 : 16,410.54 = 7,428.42 : x
2. Step 2: Convert to fraction form
   10,939.90/16,410.54 = 7,428.42/x
3. Step 3: Cross multiply
   10,939.90x = 16,410.54 × 7,428.42
4. Step 4: Simplify right side
   10,939.90x = 121,904,383.55
5. Step 5: Solve for x
   x = 121,904,383.55/10,939.90
6. Step 6: Final answer
   x = 11,143.10