Finding the Fourth Proportional to 2,590.88, 3,886.34 and 859.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,590.88 : 3,886.34 = 859.50 : x
2. Step 2: Convert to fraction form
   2,590.88/3,886.34 = 859.50/x
3. Step 3: Cross multiply
   2,590.88x = 3,886.34 × 859.50
4. Step 4: Simplify right side
   2,590.88x = 3,340,304.93
5. Step 5: Solve for x
   x = 3,340,304.93/2,590.88
6. Step 6: Final answer
   x = 1,289.26