Finding the Fourth Proportional to 21,964.12, 30,309.39 and 12,405.10

Step by Step Solution

1. Step 1: Write the proportion equation
   21,964.12 : 30,309.39 = 12,405.10 : x
2. Step 2: Convert to fraction form
   21,964.12/30,309.39 = 12,405.10/x
3. Step 3: Cross multiply
   21,964.12x = 30,309.39 × 12,405.10
4. Step 4: Simplify right side
   21,964.12x = 375,991,013.89
5. Step 5: Solve for x
   x = 375,991,013.89/21,964.12
6. Step 6: Final answer
   x = 17,118.42