Finding the Fourth Proportional to 42,471.92, 63,708.04 and 12,890

Step by Step Solution

1. Step 1: Write the proportion equation
   42,471.92 : 63,708.04 = 12,890 : x
2. Step 2: Convert to fraction form
   42,471.92/63,708.04 = 12,890/x
3. Step 3: Cross multiply
   42,471.92x = 63,708.04 × 12,890
4. Step 4: Simplify right side
   42,471.92x = 821,196,635.60
5. Step 5: Solve for x
   x = 821,196,635.60/42,471.92
6. Step 6: Final answer
   x = 19,335.05