Finding the Fourth Proportional to 8,428, 12,636.24 and 5,142.24

Step by Step Solution

1. Step 1: Write the proportion equation
   8,428 : 12,636.24 = 5,142.24 : x
2. Step 2: Convert to fraction form
   8,428/12,636.24 = 5,142.24/x
3. Step 3: Cross multiply
   8,428x = 12,636.24 × 5,142.24
4. Step 4: Simplify right side
   8,428x = 64,978,578.78
5. Step 5: Solve for x
   x = 64,978,578.78/8,428
6. Step 6: Final answer
   x = 7,709.85