Finding the Fourth Proportional to 1,098.78, 1,648.56 and 514.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,098.78 : 1,648.56 = 514.05 : x
2. Step 2: Convert to fraction form
   1,098.78/1,648.56 = 514.05/x
3. Step 3: Cross multiply
   1,098.78x = 1,648.56 × 514.05
4. Step 4: Simplify right side
   1,098.78x = 847,442.27
5. Step 5: Solve for x
   x = 847,442.27/1,098.78
6. Step 6: Final answer
   x = 771.26