Finding the Fourth Proportional to 31,005.06, 42,785.18 and 16,857.78

Step by Step Solution

1. Step 1: Write the proportion equation
   31,005.06 : 42,785.18 = 16,857.78 : x
2. Step 2: Convert to fraction form
   31,005.06/42,785.18 = 16,857.78/x
3. Step 3: Cross multiply
   31,005.06x = 42,785.18 × 16,857.78
4. Step 4: Simplify right side
   31,005.06x = 721,263,151.70
5. Step 5: Solve for x
   x = 721,263,151.70/31,005.06
6. Step 6: Final answer
   x = 23,262.76