Finding the Fourth Proportional to 3,389.52, 5,085.78 and 2,156.60

Step by Step Solution

1. Step 1: Write the proportion equation
   3,389.52 : 5,085.78 = 2,156.60 : x
2. Step 2: Convert to fraction form
   3,389.52/5,085.78 = 2,156.60/x
3. Step 3: Cross multiply
   3,389.52x = 5,085.78 × 2,156.60
4. Step 4: Simplify right side
   3,389.52x = 10,967,993.15
5. Step 5: Solve for x
   x = 10,967,993.15/3,389.52
6. Step 6: Final answer
   x = 3,235.85