Finding the Third Proportional to 85.78 and 110.53

Step by Step Solution

1. Step 1: Write the proportion equation
   85.78 : 110.53 = 110.53 : x
2. Step 2: Convert to fraction form
   85.78/110.53 = 110.53/x
3. Step 3: Cross multiply
   85.78x = 110.53 × 110.53
4. Step 4: Simplify right side
   85.78x = 12,217.16
5. Step 5: Solve for x
   x = 12,217.16/85.78
6. Step 6: Final answer
   x = 142.42