Finding the Fourth Proportional to 3,833.39, 5,290.42 and 2,155.20

Step by Step Solution

1. Step 1: Write the proportion equation
   3,833.39 : 5,290.42 = 2,155.20 : x
2. Step 2: Convert to fraction form
   3,833.39/5,290.42 = 2,155.20/x
3. Step 3: Cross multiply
   3,833.39x = 5,290.42 × 2,155.20
4. Step 4: Simplify right side
   3,833.39x = 11,401,907.80
5. Step 5: Solve for x
   x = 11,401,907.80/3,833.39
6. Step 6: Final answer
   x = 2,974.37