Finding the Third Proportional to 350.50 and 490.50

Step by Step Solution

1. Step 1: Write the proportion equation
   350.50 : 490.50 = 490.50 : x
2. Step 2: Convert to fraction form
   350.50/490.50 = 490.50/x
3. Step 3: Cross multiply
   350.50x = 490.50 × 490.50
4. Step 4: Simplify right side
   350.50x = 240,590.25
5. Step 5: Solve for x
   x = 240,590.25/350.50
6. Step 6: Final answer
   x = 686.42