Finding the Fourth Proportional to 2,139.40, 2,951.16 and 1,353.16

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.40 : 2,951.16 = 1,353.16 : x
2. Step 2: Convert to fraction form
   2,139.40/2,951.16 = 1,353.16/x
3. Step 3: Cross multiply
   2,139.40x = 2,951.16 × 1,353.16
4. Step 4: Simplify right side
   2,139.40x = 3,993,391.67
5. Step 5: Solve for x
   x = 3,993,391.67/2,139.40
6. Step 6: Final answer
   x = 1,866.59