Finding the Fourth Proportional to 12,428.50, 17,151.69 and 6,839.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,428.50 : 17,151.69 = 6,839.50 : x
2. Step 2: Convert to fraction form
   12,428.50/17,151.69 = 6,839.50/x
3. Step 3: Cross multiply
   12,428.50x = 17,151.69 × 6,839.50
4. Step 4: Simplify right side
   12,428.50x = 117,308,983.76
5. Step 5: Solve for x
   x = 117,308,983.76/12,428.50
6. Step 6: Final answer
   x = 9,438.71