Finding the Fourth Proportional to 2,606.40, 3,910.83 and 1,308.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,606.40 : 3,910.83 = 1,308.78 : x
2. Step 2: Convert to fraction form
   2,606.40/3,910.83 = 1,308.78/x
3. Step 3: Cross multiply
   2,606.40x = 3,910.83 × 1,308.78
4. Step 4: Simplify right side
   2,606.40x = 5,118,416.09
5. Step 5: Solve for x
   x = 5,118,416.09/2,606.40
6. Step 6: Final answer
   x = 1,963.79