Finding the Fourth Proportional to 2,587.20, 3,878.82 and 1,289.58

Step by Step Solution

1. Step 1: Write the proportion equation
   2,587.20 : 3,878.82 = 1,289.58 : x
2. Step 2: Convert to fraction form
   2,587.20/3,878.82 = 1,289.58/x
3. Step 3: Cross multiply
   2,587.20x = 3,878.82 × 1,289.58
4. Step 4: Simplify right side
   2,587.20x = 5,002,048.70
5. Step 5: Solve for x
   x = 5,002,048.70/2,587.20
6. Step 6: Final answer
   x = 1,933.38