Finding the Third Proportional to 320.50 and 470.50

Step by Step Solution

1. Step 1: Write the proportion equation
   320.50 : 470.50 = 470.50 : x
2. Step 2: Convert to fraction form
   320.50/470.50 = 470.50/x
3. Step 3: Cross multiply
   320.50x = 470.50 × 470.50
4. Step 4: Simplify right side
   320.50x = 221,370.25
5. Step 5: Solve for x
   x = 221,370.25/320.50
6. Step 6: Final answer
   x = 690.70