Finding the Fourth Proportional to 82.17, 123.17 and 38.79

Step by Step Solution

1. Step 1: Write the proportion equation
   82.17 : 123.17 = 38.79 : x
2. Step 2: Convert to fraction form
   82.17/123.17 = 38.79/x
3. Step 3: Cross multiply
   82.17x = 123.17 × 38.79
4. Step 4: Simplify right side
   82.17x = 4,777.57
5. Step 5: Solve for x
   x = 4,777.57/82.17
6. Step 6: Final answer
   x = 58.14