Finding the Fourth Proportional to 2,818.38, 4,227.78 and 870.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,818.38 : 4,227.78 = 870.57 : x
2. Step 2: Convert to fraction form
   2,818.38/4,227.78 = 870.57/x
3. Step 3: Cross multiply
   2,818.38x = 4,227.78 × 870.57
4. Step 4: Simplify right side
   2,818.38x = 3,680,578.43
5. Step 5: Solve for x
   x = 3,680,578.43/2,818.38
6. Step 6: Final answer
   x = 1,305.92