Finding the Fourth Proportional to 12,786.78, 17,644.50 and 7,480.56

Step by Step Solution

1. Step 1: Write the proportion equation
   12,786.78 : 17,644.50 = 7,480.56 : x
2. Step 2: Convert to fraction form
   12,786.78/17,644.50 = 7,480.56/x
3. Step 3: Cross multiply
   12,786.78x = 17,644.50 × 7,480.56
4. Step 4: Simplify right side
   12,786.78x = 131,990,740.92
5. Step 5: Solve for x
   x = 131,990,740.92/12,786.78
6. Step 6: Final answer
   x = 10,322.44