Finding the Fourth Proportional to 31,082.74, 42,900.81 and 20,473.30

Step by Step Solution

1. Step 1: Write the proportion equation
   31,082.74 : 42,900.81 = 20,473.30 : x
2. Step 2: Convert to fraction form
   31,082.74/42,900.81 = 20,473.30/x
3. Step 3: Cross multiply
   31,082.74x = 42,900.81 × 20,473.30
4. Step 4: Simplify right side
   31,082.74x = 878,321,153.37
5. Step 5: Solve for x
   x = 878,321,153.37/31,082.74
6. Step 6: Final answer
   x = 28,257.52