Finding the Fourth Proportional to 31,006.78, 42,789.30 and 16,859.59

Step by Step Solution

1. Step 1: Write the proportion equation
   31,006.78 : 42,789.30 = 16,859.59 : x
2. Step 2: Convert to fraction form
   31,006.78/42,789.30 = 16,859.59/x
3. Step 3: Cross multiply
   31,006.78x = 42,789.30 × 16,859.59
4. Step 4: Simplify right side
   31,006.78x = 721,410,054.39
5. Step 5: Solve for x
   x = 721,410,054.39/31,006.78
6. Step 6: Final answer
   x = 23,266.20