Finding the Fourth Proportional to 14,320.80, 19,767.60 and 8,658.72

Step by Step Solution

1. Step 1: Write the proportion equation
   14,320.80 : 19,767.60 = 8,658.72 : x
2. Step 2: Convert to fraction form
   14,320.80/19,767.60 = 8,658.72/x
3. Step 3: Cross multiply
   14,320.80x = 19,767.60 × 8,658.72
4. Step 4: Simplify right side
   14,320.80x = 171,162,113.47
5. Step 5: Solve for x
   x = 171,162,113.47/14,320.80
6. Step 6: Final answer
   x = 11,951.99