Finding the Fourth Proportional to 82.49, 123.72 and 21.61

Step by Step Solution

1. Step 1: Write the proportion equation
   82.49 : 123.72 = 21.61 : x
2. Step 2: Convert to fraction form
   82.49/123.72 = 21.61/x
3. Step 3: Cross multiply
   82.49x = 123.72 × 21.61
4. Step 4: Simplify right side
   82.49x = 2,673.66
5. Step 5: Solve for x
   x = 2,673.66/82.49
6. Step 6: Final answer
   x = 32.41