Finding the Fourth Proportional to 2,128.71, 3,171.69 and 2,009.34

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.71 : 3,171.69 = 2,009.34 : x
2. Step 2: Convert to fraction form
   2,128.71/3,171.69 = 2,009.34/x
3. Step 3: Cross multiply
   2,128.71x = 3,171.69 × 2,009.34
4. Step 4: Simplify right side
   2,128.71x = 6,373,003.58
5. Step 5: Solve for x
   x = 6,373,003.58/2,128.71
6. Step 6: Final answer
   x = 2,993.83