Finding the Fourth Proportional to 2,811.69, 3,878.61 and 1,691.96

Step by Step Solution

1. Step 1: Write the proportion equation
   2,811.69 : 3,878.61 = 1,691.96 : x
2. Step 2: Convert to fraction form
   2,811.69/3,878.61 = 1,691.96/x
3. Step 3: Cross multiply
   2,811.69x = 3,878.61 × 1,691.96
4. Step 4: Simplify right side
   2,811.69x = 6,562,441.78
5. Step 5: Solve for x
   x = 6,562,441.78/2,811.69
6. Step 6: Final answer
   x = 2,333.98