Finding the Fourth Proportional to 3,900.66, 5,382.63 and 2,131.89

Step by Step Solution

1. Step 1: Write the proportion equation
   3,900.66 : 5,382.63 = 2,131.89 : x
2. Step 2: Convert to fraction form
   3,900.66/5,382.63 = 2,131.89/x
3. Step 3: Cross multiply
   3,900.66x = 5,382.63 × 2,131.89
4. Step 4: Simplify right side
   3,900.66x = 11,475,175.07
5. Step 5: Solve for x
   x = 11,475,175.07/3,900.66
6. Step 6: Final answer
   x = 2,941.85