Finding the Fourth Proportional to 2,578.63, 3,868.16 and 823.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,578.63 : 3,868.16 = 823.89 : x
2. Step 2: Convert to fraction form
   2,578.63/3,868.16 = 823.89/x
3. Step 3: Cross multiply
   2,578.63x = 3,868.16 × 823.89
4. Step 4: Simplify right side
   2,578.63x = 3,186,919.00
5. Step 5: Solve for x
   x = 3,186,919.00/2,578.63
6. Step 6: Final answer
   x = 1,235.90