Finding the Fourth Proportional to 82.68, 123.87 and 80.79

Step by Step Solution

1. Step 1: Write the proportion equation
   82.68 : 123.87 = 80.79 : x
2. Step 2: Convert to fraction form
   82.68/123.87 = 80.79/x
3. Step 3: Cross multiply
   82.68x = 123.87 × 80.79
4. Step 4: Simplify right side
   82.68x = 10,007.46
5. Step 5: Solve for x
   x = 10,007.46/82.68
6. Step 6: Final answer
   x = 121.04