Finding the Fourth Proportional to 1,109.85, 1,530.78 and 689.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.85 : 1,530.78 = 689.73 : x
2. Step 2: Convert to fraction form
   1,109.85/1,530.78 = 689.73/x
3. Step 3: Cross multiply
   1,109.85x = 1,530.78 × 689.73
4. Step 4: Simplify right side
   1,109.85x = 1,055,824.89
5. Step 5: Solve for x
   x = 1,055,824.89/1,109.85
6. Step 6: Final answer
   x = 951.32