Finding the Fourth Proportional to 82.71, 124.85 and 82.31

Step by Step Solution

1. Step 1: Write the proportion equation
   82.71 : 124.85 = 82.31 : x
2. Step 2: Convert to fraction form
   82.71/124.85 = 82.31/x
3. Step 3: Cross multiply
   82.71x = 124.85 × 82.31
4. Step 4: Simplify right side
   82.71x = 10,275.37
5. Step 5: Solve for x
   x = 10,275.37/82.71
6. Step 6: Final answer
   x = 124.23