Finding the Fourth Proportional to 2,381.47, 3,568.27 and 820.65

Step by Step Solution

1. Step 1: Write the proportion equation
   2,381.47 : 3,568.27 = 820.65 : x
2. Step 2: Convert to fraction form
   2,381.47/3,568.27 = 820.65/x
3. Step 3: Cross multiply
   2,381.47x = 3,568.27 × 820.65
4. Step 4: Simplify right side
   2,381.47x = 2,928,300.78
5. Step 5: Solve for x
   x = 2,928,300.78/2,381.47
6. Step 6: Final answer
   x = 1,229.62