Finding the Fourth Proportional to 22,390.72, 30,903.06 and 12,964.48

Step by Step Solution

1. Step 1: Write the proportion equation
   22,390.72 : 30,903.06 = 12,964.48 : x
2. Step 2: Convert to fraction form
   22,390.72/30,903.06 = 12,964.48/x
3. Step 3: Cross multiply
   22,390.72x = 30,903.06 × 12,964.48
4. Step 4: Simplify right side
   22,390.72x = 400,642,103.31
5. Step 5: Solve for x
   x = 400,642,103.31/22,390.72
6. Step 6: Final answer
   x = 17,893.22