Finding the Fourth Proportional to 82.14, 123.20 and 30.79

Step by Step Solution

1. Step 1: Write the proportion equation
   82.14 : 123.20 = 30.79 : x
2. Step 2: Convert to fraction form
   82.14/123.20 = 30.79/x
3. Step 3: Cross multiply
   82.14x = 123.20 × 30.79
4. Step 4: Simplify right side
   82.14x = 3,793.33
5. Step 5: Solve for x
   x = 3,793.33/82.14
6. Step 6: Final answer
   x = 46.18