Finding the Fourth Proportional to 2,813.20, 4,218.72 and 963.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,813.20 : 4,218.72 = 963.76 : x
2. Step 2: Convert to fraction form
   2,813.20/4,218.72 = 963.76/x
3. Step 3: Cross multiply
   2,813.20x = 4,218.72 × 963.76
4. Step 4: Simplify right side
   2,813.20x = 4,065,833.59
5. Step 5: Solve for x
   x = 4,065,833.59/2,813.20
6. Step 6: Final answer
   x = 1,445.27