Finding the Fourth Proportional to 12,443.76, 17,173.89 and 7,728.75

Step by Step Solution

1. Step 1: Write the proportion equation
   12,443.76 : 17,173.89 = 7,728.75 : x
2. Step 2: Convert to fraction form
   12,443.76/17,173.89 = 7,728.75/x
3. Step 3: Cross multiply
   12,443.76x = 17,173.89 × 7,728.75
4. Step 4: Simplify right side
   12,443.76x = 132,732,702.34
5. Step 5: Solve for x
   x = 132,732,702.34/12,443.76
6. Step 6: Final answer
   x = 10,666.61