Finding the Third Proportional to 82.78 and 122.91

Step by Step Solution

1. Step 1: Write the proportion equation
   82.78 : 122.91 = 122.91 : x
2. Step 2: Convert to fraction form
   82.78/122.91 = 122.91/x
3. Step 3: Cross multiply
   82.78x = 122.91 × 122.91
4. Step 4: Simplify right side
   82.78x = 15,105.95
5. Step 5: Solve for x
   x = 15,105.95/82.78
6. Step 6: Final answer
   x = 182.48