Finding the Fourth Proportional to 82.32, 123.40 and 28.19

Step by Step Solution

1. Step 1: Write the proportion equation
   82.32 : 123.40 = 28.19 : x
2. Step 2: Convert to fraction form
   82.32/123.40 = 28.19/x
3. Step 3: Cross multiply
   82.32x = 123.40 × 28.19
4. Step 4: Simplify right side
   82.32x = 3,477.89
5. Step 5: Solve for x
   x = 3,477.89/82.32
6. Step 6: Final answer
   x = 42.25