Finding the Fourth Proportional to 2,659.56, 3,987.82 and 810.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,659.56 : 3,987.82 = 810.15 : x
2. Step 2: Convert to fraction form
   2,659.56/3,987.82 = 810.15/x
3. Step 3: Cross multiply
   2,659.56x = 3,987.82 × 810.15
4. Step 4: Simplify right side
   2,659.56x = 3,230,732.37
5. Step 5: Solve for x
   x = 3,230,732.37/2,659.56
6. Step 6: Final answer
   x = 1,214.76