Finding the Third Proportional to 85.50 and 109.75

Step by Step Solution

1. Step 1: Write the proportion equation
   85.50 : 109.75 = 109.75 : x
2. Step 2: Convert to fraction form
   85.50/109.75 = 109.75/x
3. Step 3: Cross multiply
   85.50x = 109.75 × 109.75
4. Step 4: Simplify right side
   85.50x = 12,045.06
5. Step 5: Solve for x
   x = 12,045.06/85.50
6. Step 6: Final answer
   x = 140.88