Finding the Fourth Proportional to 2,859.89, 4,290.37 and 911.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,859.89 : 4,290.37 = 911.57 : x
2. Step 2: Convert to fraction form
   2,859.89/4,290.37 = 911.57/x
3. Step 3: Cross multiply
   2,859.89x = 4,290.37 × 911.57
4. Step 4: Simplify right side
   2,859.89x = 3,910,948.85
5. Step 5: Solve for x
   x = 3,910,948.85/2,859.89
6. Step 6: Final answer
   x = 1,367.52