Finding the Fourth Proportional to 2,820.52, 3,891.61 and 1,811.77

Step by Step Solution

1. Step 1: Write the proportion equation
   2,820.52 : 3,891.61 = 1,811.77 : x
2. Step 2: Convert to fraction form
   2,820.52/3,891.61 = 1,811.77/x
3. Step 3: Cross multiply
   2,820.52x = 3,891.61 × 1,811.77
4. Step 4: Simplify right side
   2,820.52x = 7,050,694.79
5. Step 5: Solve for x
   x = 7,050,694.79/2,820.52
6. Step 6: Final answer
   x = 2,499.78