Finding the Fourth Proportional to 23,048.40, 31,809.82 and 12,978.80

Step by Step Solution

1. Step 1: Write the proportion equation
   23,048.40 : 31,809.82 = 12,978.80 : x
2. Step 2: Convert to fraction form
   23,048.40/31,809.82 = 12,978.80/x
3. Step 3: Cross multiply
   23,048.40x = 31,809.82 × 12,978.80
4. Step 4: Simplify right side
   23,048.40x = 412,853,291.82
5. Step 5: Solve for x
   x = 412,853,291.82/23,048.40
6. Step 6: Final answer
   x = 17,912.45