Finding the Fourth Proportional to 2,086.94, 3,128.59 and 1,780.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.94 : 3,128.59 = 1,780.76 : x
2. Step 2: Convert to fraction form
   2,086.94/3,128.59 = 1,780.76/x
3. Step 3: Cross multiply
   2,086.94x = 3,128.59 × 1,780.76
4. Step 4: Simplify right side
   2,086.94x = 5,571,267.93
5. Step 5: Solve for x
   x = 5,571,267.93/2,086.94
6. Step 6: Final answer
   x = 2,669.59