Finding the Fourth Proportional to 31,086.24, 42,886.20 and 21,660.27

Step by Step Solution

1. Step 1: Write the proportion equation
   31,086.24 : 42,886.20 = 21,660.27 : x
2. Step 2: Convert to fraction form
   31,086.24/42,886.20 = 21,660.27/x
3. Step 3: Cross multiply
   31,086.24x = 42,886.20 × 21,660.27
4. Step 4: Simplify right side
   31,086.24x = 928,926,671.27
5. Step 5: Solve for x
   x = 928,926,671.27/31,086.24
6. Step 6: Final answer
   x = 29,882.25