Finding the Third Proportional to 67.28 and 86.50

Step by Step Solution

1. Step 1: Write the proportion equation
   67.28 : 86.50 = 86.50 : x
2. Step 2: Convert to fraction form
   67.28/86.50 = 86.50/x
3. Step 3: Cross multiply
   67.28x = 86.50 × 86.50
4. Step 4: Simplify right side
   67.28x = 7,481.83
5. Step 5: Solve for x
   x = 7,481.83/67.28
6. Step 6: Final answer
   x = 111.21