Finding the Fourth Proportional to 3,578.39, 4,939.52 and 2,086.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,578.39 : 4,939.52 = 2,086.78 : x
2. Step 2: Convert to fraction form
   3,578.39/4,939.52 = 2,086.78/x
3. Step 3: Cross multiply
   3,578.39x = 4,939.52 × 2,086.78
4. Step 4: Simplify right side
   3,578.39x = 10,307,684.41
5. Step 5: Solve for x
   x = 10,307,684.41/3,578.39
6. Step 6: Final answer
   x = 2,880.53