Finding the Fourth Proportional to 21,241.10, 31,817.89 and 12,454.83

Step by Step Solution

1. Step 1: Write the proportion equation
   21,241.10 : 31,817.89 = 12,454.83 : x
2. Step 2: Convert to fraction form
   21,241.10/31,817.89 = 12,454.83/x
3. Step 3: Cross multiply
   21,241.10x = 31,817.89 × 12,454.83
4. Step 4: Simplify right side
   21,241.10x = 396,286,410.91
5. Step 5: Solve for x
   x = 396,286,410.91/21,241.10
6. Step 6: Final answer
   x = 18,656.59