Finding the Fourth Proportional to 2,275.08, 3,139.67 and 1,391.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,275.08 : 3,139.67 = 1,391.37 : x
2. Step 2: Convert to fraction form
   2,275.08/3,139.67 = 1,391.37/x
3. Step 3: Cross multiply
   2,275.08x = 3,139.67 × 1,391.37
4. Step 4: Simplify right side
   2,275.08x = 4,368,435.69
5. Step 5: Solve for x
   x = 4,368,435.69/2,275.08
6. Step 6: Final answer
   x = 1,920.12