Finding the Fourth Proportional to 3,897.33, 5,378.43 and 2,405.31

Step by Step Solution

1. Step 1: Write the proportion equation
   3,897.33 : 5,378.43 = 2,405.31 : x
2. Step 2: Convert to fraction form
   3,897.33/5,378.43 = 2,405.31/x
3. Step 3: Cross multiply
   3,897.33x = 5,378.43 × 2,405.31
4. Step 4: Simplify right side
   3,897.33x = 12,936,791.46
5. Step 5: Solve for x
   x = 12,936,791.46/3,897.33
6. Step 6: Final answer
   x = 3,319.40