Finding the Fourth Proportional to 800.82, 1,200.42 and 338.94

Step by Step Solution

1. Step 1: Write the proportion equation
   800.82 : 1,200.42 = 338.94 : x
2. Step 2: Convert to fraction form
   800.82/1,200.42 = 338.94/x
3. Step 3: Cross multiply
   800.82x = 1,200.42 × 338.94
4. Step 4: Simplify right side
   800.82x = 406,870.35
5. Step 5: Solve for x
   x = 406,870.35/800.82
6. Step 6: Final answer
   x = 508.07