Finding the Fourth Proportional to 82.19, 123.21 and 28.06

Step by Step Solution

1. Step 1: Write the proportion equation
   82.19 : 123.21 = 28.06 : x
2. Step 2: Convert to fraction form
   82.19/123.21 = 28.06/x
3. Step 3: Cross multiply
   82.19x = 123.21 × 28.06
4. Step 4: Simplify right side
   82.19x = 3,456.96
5. Step 5: Solve for x
   x = 3,456.96/82.19
6. Step 6: Final answer
   x = 42.06