Finding the Fourth Proportional to 2,139.89, 2,953.11 and 1,208.39

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.89 : 2,953.11 = 1,208.39 : x
2. Step 2: Convert to fraction form
   2,139.89/2,953.11 = 1,208.39/x
3. Step 3: Cross multiply
   2,139.89x = 2,953.11 × 1,208.39
4. Step 4: Simplify right side
   2,139.89x = 3,568,502.55
5. Step 5: Solve for x
   x = 3,568,502.55/2,139.89
6. Step 6: Final answer
   x = 1,667.61