Finding the Fourth Proportional to 3,900.05, 5,382.15 and 2,131.77

Step by Step Solution

1. Step 1: Write the proportion equation
   3,900.05 : 5,382.15 = 2,131.77 : x
2. Step 2: Convert to fraction form
   3,900.05/5,382.15 = 2,131.77/x
3. Step 3: Cross multiply
   3,900.05x = 5,382.15 × 2,131.77
4. Step 4: Simplify right side
   3,900.05x = 11,473,487.82
5. Step 5: Solve for x
   x = 11,473,487.82/3,900.05
6. Step 6: Final answer
   x = 2,941.88