Finding the Fourth Proportional to 12,640.72, 18,963.78 and 4,851.76

Step by Step Solution

1. Step 1: Write the proportion equation
   12,640.72 : 18,963.78 = 4,851.76 : x
2. Step 2: Convert to fraction form
   12,640.72/18,963.78 = 4,851.76/x
3. Step 3: Cross multiply
   12,640.72x = 18,963.78 × 4,851.76
4. Step 4: Simplify right side
   12,640.72x = 92,007,709.25
5. Step 5: Solve for x
   x = 92,007,709.25/12,640.72
6. Step 6: Final answer
   x = 7,278.68