Finding the Fourth Proportional to 2,615.94, 3,916.89 and 1,380.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,615.94 : 3,916.89 = 1,380.78 : x
2. Step 2: Convert to fraction form
   2,615.94/3,916.89 = 1,380.78/x
3. Step 3: Cross multiply
   2,615.94x = 3,916.89 × 1,380.78
4. Step 4: Simplify right side
   2,615.94x = 5,408,363.37
5. Step 5: Solve for x
   x = 5,408,363.37/2,615.94
6. Step 6: Final answer
   x = 2,067.46