Finding the Fourth Proportional to 2,590.76, 3,886.68 and 859.34

Step by Step Solution

1. Step 1: Write the proportion equation
   2,590.76 : 3,886.68 = 859.34 : x
2. Step 2: Convert to fraction form
   2,590.76/3,886.68 = 859.34/x
3. Step 3: Cross multiply
   2,590.76x = 3,886.68 × 859.34
4. Step 4: Simplify right side
   2,590.76x = 3,339,979.59
5. Step 5: Solve for x
   x = 3,339,979.59/2,590.76
6. Step 6: Final answer
   x = 1,289.19