Finding the Fourth Proportional to 2,578.79, 3,867.04 and 823.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,578.79 : 3,867.04 = 823.47 : x
2. Step 2: Convert to fraction form
   2,578.79/3,867.04 = 823.47/x
3. Step 3: Cross multiply
   2,578.79x = 3,867.04 × 823.47
4. Step 4: Simplify right side
   2,578.79x = 3,184,391.43
5. Step 5: Solve for x
   x = 3,184,391.43/2,578.79
6. Step 6: Final answer
   x = 1,234.84