Finding the Fourth Proportional to 82.14, 123.21 and 28.05

Step by Step Solution

1. Step 1: Write the proportion equation
   82.14 : 123.21 = 28.05 : x
2. Step 2: Convert to fraction form
   82.14/123.21 = 28.05/x
3. Step 3: Cross multiply
   82.14x = 123.21 × 28.05
4. Step 4: Simplify right side
   82.14x = 3,456.04
5. Step 5: Solve for x
   x = 3,456.04/82.14
6. Step 6: Final answer
   x = 42.08