Finding the Fourth Proportional to 2,619.56, 3,929.38 and 671.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,619.56 : 3,929.38 = 671.72 : x
2. Step 2: Convert to fraction form
   2,619.56/3,929.38 = 671.72/x
3. Step 3: Cross multiply
   2,619.56x = 3,929.38 × 671.72
4. Step 4: Simplify right side
   2,619.56x = 2,639,443.13
5. Step 5: Solve for x
   x = 2,639,443.13/2,619.56
6. Step 6: Final answer
   x = 1,007.59