Finding the Fourth Proportional to 8,519.28, 12,763.56 and 7,131.12

Step by Step Solution

1. Step 1: Write the proportion equation
   8,519.28 : 12,763.56 = 7,131.12 : x
2. Step 2: Convert to fraction form
   8,519.28/12,763.56 = 7,131.12/x
3. Step 3: Cross multiply
   8,519.28x = 12,763.56 × 7,131.12
4. Step 4: Simplify right side
   8,519.28x = 91,018,477.99
5. Step 5: Solve for x
   x = 91,018,477.99/8,519.28
6. Step 6: Final answer
   x = 10,683.82