Finding the Fourth Proportional to 2,575.45, 3,864.27 and 820.59

Step by Step Solution

1. Step 1: Write the proportion equation
   2,575.45 : 3,864.27 = 820.59 : x
2. Step 2: Convert to fraction form
   2,575.45/3,864.27 = 820.59/x
3. Step 3: Cross multiply
   2,575.45x = 3,864.27 × 820.59
4. Step 4: Simplify right side
   2,575.45x = 3,170,981.32
5. Step 5: Solve for x
   x = 3,170,981.32/2,575.45
6. Step 6: Final answer
   x = 1,231.24