Finding the Fourth Proportional to 10,428.78, 14,391.63 and 5,712.96

Step by Step Solution

1. Step 1: Write the proportion equation
   10,428.78 : 14,391.63 = 5,712.96 : x
2. Step 2: Convert to fraction form
   10,428.78/14,391.63 = 5,712.96/x
3. Step 3: Cross multiply
   10,428.78x = 14,391.63 × 5,712.96
4. Step 4: Simplify right side
   10,428.78x = 82,218,806.52
5. Step 5: Solve for x
   x = 82,218,806.52/10,428.78
6. Step 6: Final answer
   x = 7,883.84