Finding the Fourth Proportional to 2,590.89, 3,861.33 and 2,586.77

Step by Step Solution

1. Step 1: Write the proportion equation
   2,590.89 : 3,861.33 = 2,586.77 : x
2. Step 2: Convert to fraction form
   2,590.89/3,861.33 = 2,586.77/x
3. Step 3: Cross multiply
   2,590.89x = 3,861.33 × 2,586.77
4. Step 4: Simplify right side
   2,590.89x = 9,988,372.60
5. Step 5: Solve for x
   x = 9,988,372.60/2,590.89
6. Step 6: Final answer
   x = 3,855.19