Finding the Fourth Proportional to 1,098.80, 1,516.41 and 626.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,098.80 : 1,516.41 = 626.78 : x
2. Step 2: Convert to fraction form
   1,098.80/1,516.41 = 626.78/x
3. Step 3: Cross multiply
   1,098.80x = 1,516.41 × 626.78
4. Step 4: Simplify right side
   1,098.80x = 950,447.88
5. Step 5: Solve for x
   x = 950,447.88/1,098.80
6. Step 6: Final answer
   x = 864.99