Finding the Fourth Proportional to 21,834.76, 30,133.20 and 12,405.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,834.76 : 30,133.20 = 12,405.28 : x
2. Step 2: Convert to fraction form
   21,834.76/30,133.20 = 12,405.28/x
3. Step 3: Cross multiply
   21,834.76x = 30,133.20 × 12,405.28
4. Step 4: Simplify right side
   21,834.76x = 373,810,783.30
5. Step 5: Solve for x
   x = 373,810,783.30/21,834.76
6. Step 6: Final answer
   x = 17,119.99