Finding the Third Proportional to 328.69 and 499.78

Step by Step Solution

1. Step 1: Write the proportion equation
   328.69 : 499.78 = 499.78 : x
2. Step 2: Convert to fraction form
   328.69/499.78 = 499.78/x
3. Step 3: Cross multiply
   328.69x = 499.78 × 499.78
4. Step 4: Simplify right side
   328.69x = 249,781.30
5. Step 5: Solve for x
   x = 249,781.30/328.69
6. Step 6: Final answer
   x = 759.94