Finding the Fourth Proportional to 21,196.35, 31,751.33 and 12,285.68

Step by Step Solution

1. Step 1: Write the proportion equation
   21,196.35 : 31,751.33 = 12,285.68 : x
2. Step 2: Convert to fraction form
   21,196.35/31,751.33 = 12,285.68/x
3. Step 3: Cross multiply
   21,196.35x = 31,751.33 × 12,285.68
4. Step 4: Simplify right side
   21,196.35x = 390,086,459.77
5. Step 5: Solve for x
   x = 390,086,459.77/21,196.35
6. Step 6: Final answer
   x = 18,403.47