Finding the Fourth Proportional to 2,591.75, 3,888.23 and 860.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,591.75 : 3,888.23 = 860.38 : x
2. Step 2: Convert to fraction form
   2,591.75/3,888.23 = 860.38/x
3. Step 3: Cross multiply
   2,591.75x = 3,888.23 × 860.38
4. Step 4: Simplify right side
   2,591.75x = 3,345,355.33
5. Step 5: Solve for x
   x = 3,345,355.33/2,591.75
6. Step 6: Final answer
   x = 1,290.77