Finding the Third Proportional to 104.78 and 136.91

Step by Step Solution

1. Step 1: Write the proportion equation
   104.78 : 136.91 = 136.91 : x
2. Step 2: Convert to fraction form
   104.78/136.91 = 136.91/x
3. Step 3: Cross multiply
   104.78x = 136.91 × 136.91
4. Step 4: Simplify right side
   104.78x = 18,743.32
5. Step 5: Solve for x
   x = 18,743.32/104.78
6. Step 6: Final answer
   x = 178.88