Finding the Fourth Proportional to 8,521.24, 12,780.78 and 3,330.76

Step by Step Solution

1. Step 1: Write the proportion equation
   8,521.24 : 12,780.78 = 3,330.76 : x
2. Step 2: Convert to fraction form
   8,521.24/12,780.78 = 3,330.76/x
3. Step 3: Cross multiply
   8,521.24x = 12,780.78 × 3,330.76
4. Step 4: Simplify right side
   8,521.24x = 42,569,710.79
5. Step 5: Solve for x
   x = 42,569,710.79/8,521.24
6. Step 6: Final answer
   x = 4,995.72