Finding the Fourth Proportional to 1,108.80, 1,662.72 and 338.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,108.80 : 1,662.72 = 338.88 : x
2. Step 2: Convert to fraction form
   1,108.80/1,662.72 = 338.88/x
3. Step 3: Cross multiply
   1,108.80x = 1,662.72 × 338.88
4. Step 4: Simplify right side
   1,108.80x = 563,462.55
5. Step 5: Solve for x
   x = 563,462.55/1,108.80
6. Step 6: Final answer
   x = 508.17