Finding the Fourth Proportional to 5,889.57, 8,128.76 and 3,900.21

Step by Step Solution

1. Step 1: Write the proportion equation
   5,889.57 : 8,128.76 = 3,900.21 : x
2. Step 2: Convert to fraction form
   5,889.57/8,128.76 = 3,900.21/x
3. Step 3: Cross multiply
   5,889.57x = 8,128.76 × 3,900.21
4. Step 4: Simplify right side
   5,889.57x = 31,703,871.04
5. Step 5: Solve for x
   x = 31,703,871.04/5,889.57
6. Step 6: Final answer
   x = 5,383.05