Finding the Fourth Proportional to 12,787.89, 17,643.06 and 7,478.95

Step by Step Solution

1. Step 1: Write the proportion equation
   12,787.89 : 17,643.06 = 7,478.95 : x
2. Step 2: Convert to fraction form
   12,787.89/17,643.06 = 7,478.95/x
3. Step 3: Cross multiply
   12,787.89x = 17,643.06 × 7,478.95
4. Step 4: Simplify right side
   12,787.89x = 131,951,563.59
5. Step 5: Solve for x
   x = 131,951,563.59/12,787.89
6. Step 6: Final answer
   x = 10,318.48