Finding the Fourth Proportional to 31,059.87, 42,851.68 and 20,311.03

Step by Step Solution

1. Step 1: Write the proportion equation
   31,059.87 : 42,851.68 = 20,311.03 : x
2. Step 2: Convert to fraction form
   31,059.87/42,851.68 = 20,311.03/x
3. Step 3: Cross multiply
   31,059.87x = 42,851.68 × 20,311.03
4. Step 4: Simplify right side
   31,059.87x = 870,361,758.03
5. Step 5: Solve for x
   x = 870,361,758.03/31,059.87
6. Step 6: Final answer
   x = 28,022.07