Finding the Fourth Proportional to 2,573.64, 3,859.31 and 818.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,573.64 : 3,859.31 = 818.31 : x
2. Step 2: Convert to fraction form
   2,573.64/3,859.31 = 818.31/x
3. Step 3: Cross multiply
   2,573.64x = 3,859.31 × 818.31
4. Step 4: Simplify right side
   2,573.64x = 3,158,128.48
5. Step 5: Solve for x
   x = 3,158,128.48/2,573.64
6. Step 6: Final answer
   x = 1,227.11