Finding the Fourth Proportional to 30,789.48, 42,479.82 and 18,840.36

Step by Step Solution

1. Step 1: Write the proportion equation
   30,789.48 : 42,479.82 = 18,840.36 : x
2. Step 2: Convert to fraction form
   30,789.48/42,479.82 = 18,840.36/x
3. Step 3: Cross multiply
   30,789.48x = 42,479.82 × 18,840.36
4. Step 4: Simplify right side
   30,789.48x = 800,335,101.54
5. Step 5: Solve for x
   x = 800,335,101.54/30,789.48
6. Step 6: Final answer
   x = 25,993.78