Finding the Fourth Proportional to 10,438.72, 15,649.28 and 7,143.68

Step by Step Solution

1. Step 1: Write the proportion equation
   10,438.72 : 15,649.28 = 7,143.68 : x
2. Step 2: Convert to fraction form
   10,438.72/15,649.28 = 7,143.68/x
3. Step 3: Cross multiply
   10,438.72x = 15,649.28 × 7,143.68
4. Step 4: Simplify right side
   10,438.72x = 111,793,448.55
5. Step 5: Solve for x
   x = 111,793,448.55/10,438.72
6. Step 6: Final answer
   x = 10,709.50