Finding the Fourth Proportional to 2,565.58, 3,848.89 and 810.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,565.58 : 3,848.89 = 810.86 : x
2. Step 2: Convert to fraction form
   2,565.58/3,848.89 = 810.86/x
3. Step 3: Cross multiply
   2,565.58x = 3,848.89 × 810.86
4. Step 4: Simplify right side
   2,565.58x = 3,120,910.95
5. Step 5: Solve for x
   x = 3,120,910.95/2,565.58
6. Step 6: Final answer
   x = 1,216.45