Finding the Fourth Proportional to 2,155.20, 3,233.70 and 1,289.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.20 : 3,233.70 = 1,289.50 : x
2. Step 2: Convert to fraction form
   2,155.20/3,233.70 = 1,289.50/x
3. Step 3: Cross multiply
   2,155.20x = 3,233.70 × 1,289.50
4. Step 4: Simplify right side
   2,155.20x = 4,169,856.15
5. Step 5: Solve for x
   x = 4,169,856.15/2,155.20
6. Step 6: Final answer
   x = 1,934.79