Finding the Fourth Proportional to 31,084.74, 42,903.57 and 20,475.30

Step by Step Solution

1. Step 1: Write the proportion equation
   31,084.74 : 42,903.57 = 20,475.30 : x
2. Step 2: Convert to fraction form
   31,084.74/42,903.57 = 20,475.30/x
3. Step 3: Cross multiply
   31,084.74x = 42,903.57 × 20,475.30
4. Step 4: Simplify right side
   31,084.74x = 878,463,466.82
5. Step 5: Solve for x
   x = 878,463,466.82/31,084.74
6. Step 6: Final answer
   x = 28,260.28