Finding the Fourth Proportional to 10,428.81, 14,391.18 and 5,712.18

Step by Step Solution

1. Step 1: Write the proportion equation
   10,428.81 : 14,391.18 = 5,712.18 : x
2. Step 2: Convert to fraction form
   10,428.81/14,391.18 = 5,712.18/x
3. Step 3: Cross multiply
   10,428.81x = 14,391.18 × 5,712.18
4. Step 4: Simplify right side
   10,428.81x = 82,205,010.57
5. Step 5: Solve for x
   x = 82,205,010.57/10,428.81
6. Step 6: Final answer
   x = 7,882.49