Finding the Fourth Proportional to 1,109.90, 1,665.10 and 329.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.90 : 1,665.10 = 329.96 : x
2. Step 2: Convert to fraction form
   1,109.90/1,665.10 = 329.96/x
3. Step 3: Cross multiply
   1,109.90x = 1,665.10 × 329.96
4. Step 4: Simplify right side
   1,109.90x = 549,419.73
5. Step 5: Solve for x
   x = 549,419.73/1,109.90
6. Step 6: Final answer
   x = 495.02