Finding the Fourth Proportional to 82.31, 113.28 and 71.98

Step by Step Solution

1. Step 1: Write the proportion equation
   82.31 : 113.28 = 71.98 : x
2. Step 2: Convert to fraction form
   82.31/113.28 = 71.98/x
3. Step 3: Cross multiply
   82.31x = 113.28 × 71.98
4. Step 4: Simplify right side
   82.31x = 8,153.34
5. Step 5: Solve for x
   x = 8,153.34/82.31
6. Step 6: Final answer
   x = 99.06