Finding the Fourth Proportional to 2,620.35, 3,930.32 and 865.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,620.35 : 3,930.32 = 865.18 : x
2. Step 2: Convert to fraction form
   2,620.35/3,930.32 = 865.18/x
3. Step 3: Cross multiply
   2,620.35x = 3,930.32 × 865.18
4. Step 4: Simplify right side
   2,620.35x = 3,400,441.33
5. Step 5: Solve for x
   x = 3,400,441.33/2,620.35
6. Step 6: Final answer
   x = 1,297.71