Finding the Fourth Proportional to 31,012.20, 42,796.87 and 16,865.05

Step by Step Solution

1. Step 1: Write the proportion equation
   31,012.20 : 42,796.87 = 16,865.05 : x
2. Step 2: Convert to fraction form
   31,012.20/42,796.87 = 16,865.05/x
3. Step 3: Cross multiply
   31,012.20x = 42,796.87 × 16,865.05
4. Step 4: Simplify right side
   31,012.20x = 721,771,352.39
5. Step 5: Solve for x
   x = 721,771,352.39/31,012.20
6. Step 6: Final answer
   x = 23,273.79