Finding the Fourth Proportional to 82.71, 123.39 and 80.10

Step by Step Solution

1. Step 1: Write the proportion equation
   82.71 : 123.39 = 80.10 : x
2. Step 2: Convert to fraction form
   82.71/123.39 = 80.10/x
3. Step 3: Cross multiply
   82.71x = 123.39 × 80.10
4. Step 4: Simplify right side
   82.71x = 9,883.54
5. Step 5: Solve for x
   x = 9,883.54/82.71
6. Step 6: Final answer
   x = 119.50