Finding the Fourth Proportional to 2,139.95, 3,205.68 and 1,319.83

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.95 : 3,205.68 = 1,319.83 : x
2. Step 2: Convert to fraction form
   2,139.95/3,205.68 = 1,319.83/x
3. Step 3: Cross multiply
   2,139.95x = 3,205.68 × 1,319.83
4. Step 4: Simplify right side
   2,139.95x = 4,230,939.67
5. Step 5: Solve for x
   x = 4,230,939.67/2,139.95
6. Step 6: Final answer
   x = 1,977.12