Finding the Fourth Proportional to 1,109.56, 1,664.50 and 339.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.56 : 1,664.50 = 339.96 : x
2. Step 2: Convert to fraction form
   1,109.56/1,664.50 = 339.96/x
3. Step 3: Cross multiply
   1,109.56x = 1,664.50 × 339.96
4. Step 4: Simplify right side
   1,109.56x = 565,863.42
5. Step 5: Solve for x
   x = 565,863.42/1,109.56
6. Step 6: Final answer
   x = 509.99