Finding the Fourth Proportional to 3,281.31, 4,920.52 and 1,200.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,281.31 : 4,920.52 = 1,200.78 : x
2. Step 2: Convert to fraction form
   3,281.31/4,920.52 = 1,200.78/x
3. Step 3: Cross multiply
   3,281.31x = 4,920.52 × 1,200.78
4. Step 4: Simplify right side
   3,281.31x = 5,908,441.91
5. Step 5: Solve for x
   x = 5,908,441.91/3,281.31
6. Step 6: Final answer
   x = 1,800.63