Finding the Fourth Proportional to 12,947.94, 17,871.42 and 7,644.42

Step by Step Solution

1. Step 1: Write the proportion equation
   12,947.94 : 17,871.42 = 7,644.42 : x
2. Step 2: Convert to fraction form
   12,947.94/17,871.42 = 7,644.42/x
3. Step 3: Cross multiply
   12,947.94x = 17,871.42 × 7,644.42
4. Step 4: Simplify right side
   12,947.94x = 136,616,640.48
5. Step 5: Solve for x
   x = 136,616,640.48/12,947.94
6. Step 6: Final answer
   x = 10,551.23