Finding the Fourth Proportional to 21,890.79, 30,209.25 and 12,461.19

Step by Step Solution

1. Step 1: Write the proportion equation
   21,890.79 : 30,209.25 = 12,461.19 : x
2. Step 2: Convert to fraction form
   21,890.79/30,209.25 = 12,461.19/x
3. Step 3: Cross multiply
   21,890.79x = 30,209.25 × 12,461.19
4. Step 4: Simplify right side
   21,890.79x = 376,443,204.01
5. Step 5: Solve for x
   x = 376,443,204.01/21,890.79
6. Step 6: Final answer
   x = 17,196.42