Finding the Fourth Proportional to 31,003.58, 42,786.69 and 16,856.12

Step by Step Solution

1. Step 1: Write the proportion equation
   31,003.58 : 42,786.69 = 16,856.12 : x
2. Step 2: Convert to fraction form
   31,003.58/42,786.69 = 16,856.12/x
3. Step 3: Cross multiply
   31,003.58x = 42,786.69 × 16,856.12
4. Step 4: Simplify right side
   31,003.58x = 721,217,581.04
5. Step 5: Solve for x
   x = 721,217,581.04/31,003.58
6. Step 6: Final answer
   x = 23,262.40