Finding the Fourth Proportional to 82.12, 123.28 and 71.98

Step by Step Solution

1. Step 1: Write the proportion equation
   82.12 : 123.28 = 71.98 : x
2. Step 2: Convert to fraction form
   82.12/123.28 = 71.98/x
3. Step 3: Cross multiply
   82.12x = 123.28 × 71.98
4. Step 4: Simplify right side
   82.12x = 8,873.69
5. Step 5: Solve for x
   x = 8,873.69/82.12
6. Step 6: Final answer
   x = 108.06