Finding the Fourth Proportional to 82.72, 124.07 and 28.61

Step by Step Solution

1. Step 1: Write the proportion equation
   82.72 : 124.07 = 28.61 : x
2. Step 2: Convert to fraction form
   82.72/124.07 = 28.61/x
3. Step 3: Cross multiply
   82.72x = 124.07 × 28.61
4. Step 4: Simplify right side
   82.72x = 3,548.88
5. Step 5: Solve for x
   x = 3,548.88/82.72
6. Step 6: Final answer
   x = 42.90