Finding the Third Proportional to 80.50 and 89.50

Step by Step Solution

1. Step 1: Write the proportion equation
   80.50 : 89.50 = 89.50 : x
2. Step 2: Convert to fraction form
   80.50/89.50 = 89.50/x
3. Step 3: Cross multiply
   80.50x = 89.50 × 89.50
4. Step 4: Simplify right side
   80.50x = 8,010.25
5. Step 5: Solve for x
   x = 8,010.25/80.50
6. Step 6: Final answer
   x = 99.51