Finding the Fourth Proportional to 3,940.94, 5,909.69 and 2,091.65

Step by Step Solution

1. Step 1: Write the proportion equation
   3,940.94 : 5,909.69 = 2,091.65 : x
2. Step 2: Convert to fraction form
   3,940.94/5,909.69 = 2,091.65/x
3. Step 3: Cross multiply
   3,940.94x = 5,909.69 × 2,091.65
4. Step 4: Simplify right side
   3,940.94x = 12,360,978.77
5. Step 5: Solve for x
   x = 12,360,978.77/3,940.94
6. Step 6: Final answer
   x = 3,136.55