Finding the Fourth Proportional to 3,443.20, 5,165.04 and 978.40

Step by Step Solution

1. Step 1: Write the proportion equation
   3,443.20 : 5,165.04 = 978.40 : x
2. Step 2: Convert to fraction form
   3,443.20/5,165.04 = 978.40/x
3. Step 3: Cross multiply
   3,443.20x = 5,165.04 × 978.40
4. Step 4: Simplify right side
   3,443.20x = 5,053,475.14
5. Step 5: Solve for x
   x = 5,053,475.14/3,443.20
6. Step 6: Final answer
   x = 1,467.67