Finding the Fourth Proportional to 31,006.80, 42,788.86 and 16,860

Step by Step Solution

1. Step 1: Write the proportion equation
   31,006.80 : 42,788.86 = 16,860 : x
2. Step 2: Convert to fraction form
   31,006.80/42,788.86 = 16,860/x
3. Step 3: Cross multiply
   31,006.80x = 42,788.86 × 16,860
4. Step 4: Simplify right side
   31,006.80x = 721,420,179.60
5. Step 5: Solve for x
   x = 721,420,179.60/31,006.80
6. Step 6: Final answer
   x = 23,266.52