Finding the Fourth Proportional to 9,678.29, 13,355.57 and 5,428.82

Step by Step Solution

1. Step 1: Write the proportion equation
   9,678.29 : 13,355.57 = 5,428.82 : x
2. Step 2: Convert to fraction form
   9,678.29/13,355.57 = 5,428.82/x
3. Step 3: Cross multiply
   9,678.29x = 13,355.57 × 5,428.82
4. Step 4: Simplify right side
   9,678.29x = 72,504,891.61
5. Step 5: Solve for x
   x = 72,504,891.61/9,678.29
6. Step 6: Final answer
   x = 7,491.50