Finding the Fourth Proportional to 1,109.89, 1,665.15 and 561.97

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.89 : 1,665.15 = 561.97 : x
2. Step 2: Convert to fraction form
   1,109.89/1,665.15 = 561.97/x
3. Step 3: Cross multiply
   1,109.89x = 1,665.15 × 561.97
4. Step 4: Simplify right side
   1,109.89x = 935,764.35
5. Step 5: Solve for x
   x = 935,764.35/1,109.89
6. Step 6: Final answer
   x = 843.11