Finding the Fourth Proportional to 2,391.56, 3,585.86 and 830.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,391.56 : 3,585.86 = 830.89 : x
2. Step 2: Convert to fraction form
   2,391.56/3,585.86 = 830.89/x
3. Step 3: Cross multiply
   2,391.56x = 3,585.86 × 830.89
4. Step 4: Simplify right side
   2,391.56x = 2,979,437.29
5. Step 5: Solve for x
   x = 2,979,437.29/2,391.56
6. Step 6: Final answer
   x = 1,245.82