Finding the Fourth Proportional to 20,456.12, 30,723.08 and 12,719

Step by Step Solution

1. Step 1: Write the proportion equation
   20,456.12 : 30,723.08 = 12,719 : x
2. Step 2: Convert to fraction form
   20,456.12/30,723.08 = 12,719/x
3. Step 3: Cross multiply
   20,456.12x = 30,723.08 × 12,719
4. Step 4: Simplify right side
   20,456.12x = 390,766,854.52
5. Step 5: Solve for x
   x = 390,766,854.52/20,456.12
6. Step 6: Final answer
   x = 19,102.69