Finding the Fourth Proportional to 20,786.12, 28,680.10 and 12,401

Step by Step Solution

1. Step 1: Write the proportion equation
   20,786.12 : 28,680.10 = 12,401 : x
2. Step 2: Convert to fraction form
   20,786.12/28,680.10 = 12,401/x
3. Step 3: Cross multiply
   20,786.12x = 28,680.10 × 12,401
4. Step 4: Simplify right side
   20,786.12x = 355,661,920.10
5. Step 5: Solve for x
   x = 355,661,920.10/20,786.12
6. Step 6: Final answer
   x = 17,110.55