Finding the Fourth Proportional to 2,138.27, 3,210.12 and 1,439.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,138.27 : 3,210.12 = 1,439.96 : x
2. Step 2: Convert to fraction form
   2,138.27/3,210.12 = 1,439.96/x
3. Step 3: Cross multiply
   2,138.27x = 3,210.12 × 1,439.96
4. Step 4: Simplify right side
   2,138.27x = 4,622,428.34
5. Step 5: Solve for x
   x = 4,622,428.34/2,138.27
6. Step 6: Final answer
   x = 2,161.77