Finding the Fourth Proportional to 2,620.56, 3,930.88 and 672.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,620.56 : 3,930.88 = 672.72 : x
2. Step 2: Convert to fraction form
   2,620.56/3,930.88 = 672.72/x
3. Step 3: Cross multiply
   2,620.56x = 3,930.88 × 672.72
4. Step 4: Simplify right side
   2,620.56x = 2,644,381.59
5. Step 5: Solve for x
   x = 2,644,381.59/2,620.56
6. Step 6: Final answer
   x = 1,009.09