Finding the Fourth Proportional to 978.92, 1,465.68 and 685.72

Step by Step Solution

1. Step 1: Write the proportion equation
   978.92 : 1,465.68 = 685.72 : x
2. Step 2: Convert to fraction form
   978.92/1,465.68 = 685.72/x
3. Step 3: Cross multiply
   978.92x = 1,465.68 × 685.72
4. Step 4: Simplify right side
   978.92x = 1,005,046.09
5. Step 5: Solve for x
   x = 1,005,046.09/978.92
6. Step 6: Final answer
   x = 1,026.69