Finding the Fourth Proportional to 2,620.72, 3,930.66 and 672.82

Step by Step Solution

1. Step 1: Write the proportion equation
   2,620.72 : 3,930.66 = 672.82 : x
2. Step 2: Convert to fraction form
   2,620.72/3,930.66 = 672.82/x
3. Step 3: Cross multiply
   2,620.72x = 3,930.66 × 672.82
4. Step 4: Simplify right side
   2,620.72x = 2,644,626.66
5. Step 5: Solve for x
   x = 2,644,626.66/2,620.72
6. Step 6: Final answer
   x = 1,009.12