Finding the Fourth Proportional to 2,861.28, 4,290.72 and 1,218.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,861.28 : 4,290.72 = 1,218.24 : x
2. Step 2: Convert to fraction form
   2,861.28/4,290.72 = 1,218.24/x
3. Step 3: Cross multiply
   2,861.28x = 4,290.72 × 1,218.24
4. Step 4: Simplify right side
   2,861.28x = 5,227,126.73
5. Step 5: Solve for x
   x = 5,227,126.73/2,861.28
6. Step 6: Final answer
   x = 1,826.85