Finding the Fourth Proportional to 2,586.96, 3,571.20 and 1,643.76

Step by Step Solution

1. Step 1: Write the proportion equation
   2,586.96 : 3,571.20 = 1,643.76 : x
2. Step 2: Convert to fraction form
   2,586.96/3,571.20 = 1,643.76/x
3. Step 3: Cross multiply
   2,586.96x = 3,571.20 × 1,643.76
4. Step 4: Simplify right side
   2,586.96x = 5,870,195.71
5. Step 5: Solve for x
   x = 5,870,195.71/2,586.96
6. Step 6: Final answer
   x = 2,269.15