Finding the Third Proportional to 653.50 and 728.50

Step by Step Solution

1. Step 1: Write the proportion equation
   653.50 : 728.50 = 728.50 : x
2. Step 2: Convert to fraction form
   653.50/728.50 = 728.50/x
3. Step 3: Cross multiply
   653.50x = 728.50 × 728.50
4. Step 4: Simplify right side
   653.50x = 530,712.25
5. Step 5: Solve for x
   x = 530,712.25/653.50
6. Step 6: Final answer
   x = 812.11