Finding the Fourth Proportional to 2,579.56, 3,865.98 and 1,039.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,579.56 : 3,865.98 = 1,039.72 : x
2. Step 2: Convert to fraction form
   2,579.56/3,865.98 = 1,039.72/x
3. Step 3: Cross multiply
   2,579.56x = 3,865.98 × 1,039.72
4. Step 4: Simplify right side
   2,579.56x = 4,019,536.73
5. Step 5: Solve for x
   x = 4,019,536.73/2,579.56
6. Step 6: Final answer
   x = 1,558.23