Finding the Fourth Proportional to 1,109.10, 1,530.54 and 611.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.10 : 1,530.54 = 611.78 : x
2. Step 2: Convert to fraction form
   1,109.10/1,530.54 = 611.78/x
3. Step 3: Cross multiply
   1,109.10x = 1,530.54 × 611.78
4. Step 4: Simplify right side
   1,109.10x = 936,353.76
5. Step 5: Solve for x
   x = 936,353.76/1,109.10
6. Step 6: Final answer
   x = 844.25