Finding the Fourth Proportional to 3,900.38, 5,382.42 and 2,131.98

Step by Step Solution

1. Step 1: Write the proportion equation
   3,900.38 : 5,382.42 = 2,131.98 : x
2. Step 2: Convert to fraction form
   3,900.38/5,382.42 = 2,131.98/x
3. Step 3: Cross multiply
   3,900.38x = 5,382.42 × 2,131.98
4. Step 4: Simplify right side
   3,900.38x = 11,475,211.79
5. Step 5: Solve for x
   x = 11,475,211.79/3,900.38
6. Step 6: Final answer
   x = 2,942.08