Finding the Fourth Proportional to 1,078.62, 1,618.86 and 429.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.62 : 1,618.86 = 429.82 : x
2. Step 2: Convert to fraction form
   1,078.62/1,618.86 = 429.82/x
3. Step 3: Cross multiply
   1,078.62x = 1,618.86 × 429.82
4. Step 4: Simplify right side
   1,078.62x = 695,818.41
5. Step 5: Solve for x
   x = 695,818.41/1,078.62
6. Step 6: Final answer
   x = 645.10