Finding the Fourth Proportional to 1,099.72, 1,649.94 and 551.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,099.72 : 1,649.94 = 551.80 : x
2. Step 2: Convert to fraction form
   1,099.72/1,649.94 = 551.80/x
3. Step 3: Cross multiply
   1,099.72x = 1,649.94 × 551.80
4. Step 4: Simplify right side
   1,099.72x = 910,436.89
5. Step 5: Solve for x
   x = 910,436.89/1,099.72
6. Step 6: Final answer
   x = 827.88