Finding the Third Proportional to 88.56 and 136.78

Step by Step Solution

1. Step 1: Write the proportion equation
   88.56 : 136.78 = 136.78 : x
2. Step 2: Convert to fraction form
   88.56/136.78 = 136.78/x
3. Step 3: Cross multiply
   88.56x = 136.78 × 136.78
4. Step 4: Simplify right side
   88.56x = 18,709.11
5. Step 5: Solve for x
   x = 18,709.11/88.56
6. Step 6: Final answer
   x = 211.25