Finding the Fourth Proportional to 2,145.76, 3,217.94 and 684.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,145.76 : 3,217.94 = 684.56 : x
2. Step 2: Convert to fraction form
   2,145.76/3,217.94 = 684.56/x
3. Step 3: Cross multiply
   2,145.76x = 3,217.94 × 684.56
4. Step 4: Simplify right side
   2,145.76x = 2,202,880.20
5. Step 5: Solve for x
   x = 2,202,880.20/2,145.76
6. Step 6: Final answer
   x = 1,026.62