Finding the Fourth Proportional to 6,426.56, 9,640.16 and 3,142.40

Step by Step Solution

1. Step 1: Write the proportion equation
   6,426.56 : 9,640.16 = 3,142.40 : x
2. Step 2: Convert to fraction form
   6,426.56/9,640.16 = 3,142.40/x
3. Step 3: Cross multiply
   6,426.56x = 9,640.16 × 3,142.40
4. Step 4: Simplify right side
   6,426.56x = 30,293,238.78
5. Step 5: Solve for x
   x = 30,293,238.78/6,426.56
6. Step 6: Final answer
   x = 4,713.76