Finding the Fourth Proportional to 31,128.57, 42,958.95 and 17,520.87

Step by Step Solution

1. Step 1: Write the proportion equation
   31,128.57 : 42,958.95 = 17,520.87 : x
2. Step 2: Convert to fraction form
   31,128.57/42,958.95 = 17,520.87/x
3. Step 3: Cross multiply
   31,128.57x = 42,958.95 × 17,520.87
4. Step 4: Simplify right side
   31,128.57x = 752,678,178.29
5. Step 5: Solve for x
   x = 752,678,178.29/31,128.57
6. Step 6: Final answer
   x = 24,179.66