Finding the Fourth Proportional to 1,098.78, 1,648.17 and 449.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,098.78 : 1,648.17 = 449.25 : x
2. Step 2: Convert to fraction form
   1,098.78/1,648.17 = 449.25/x
3. Step 3: Cross multiply
   1,098.78x = 1,648.17 × 449.25
4. Step 4: Simplify right side
   1,098.78x = 740,440.37
5. Step 5: Solve for x
   x = 740,440.37/1,098.78
6. Step 6: Final answer
   x = 673.88