Finding the Fourth Proportional to 82.76, 123.49 and 82.16

Step by Step Solution

1. Step 1: Write the proportion equation
   82.76 : 123.49 = 82.16 : x
2. Step 2: Convert to fraction form
   82.76/123.49 = 82.16/x
3. Step 3: Cross multiply
   82.76x = 123.49 × 82.16
4. Step 4: Simplify right side
   82.76x = 10,145.94
5. Step 5: Solve for x
   x = 10,145.94/82.76
6. Step 6: Final answer
   x = 122.59