Finding the Fourth Proportional to 82.71, 113.43 and 82.31

Step by Step Solution

1. Step 1: Write the proportion equation
   82.71 : 113.43 = 82.31 : x
2. Step 2: Convert to fraction form
   82.71/113.43 = 82.31/x
3. Step 3: Cross multiply
   82.71x = 113.43 × 82.31
4. Step 4: Simplify right side
   82.71x = 9,335.86
5. Step 5: Solve for x
   x = 9,335.86/82.71
6. Step 6: Final answer
   x = 112.87