Finding the Fourth Proportional to 1,108.72, 1,530.18 and 689.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,108.72 : 1,530.18 = 689.23 : x
2. Step 2: Convert to fraction form
   1,108.72/1,530.18 = 689.23/x
3. Step 3: Cross multiply
   1,108.72x = 1,530.18 × 689.23
4. Step 4: Simplify right side
   1,108.72x = 1,054,645.96
5. Step 5: Solve for x
   x = 1,054,645.96/1,108.72
6. Step 6: Final answer
   x = 951.23