Finding the Fourth Proportional to 2,145.72, 3,218.79 and 684.53

Step by Step Solution

1. Step 1: Write the proportion equation
   2,145.72 : 3,218.79 = 684.53 : x
2. Step 2: Convert to fraction form
   2,145.72/3,218.79 = 684.53/x
3. Step 3: Cross multiply
   2,145.72x = 3,218.79 × 684.53
4. Step 4: Simplify right side
   2,145.72x = 2,203,342.22
5. Step 5: Solve for x
   x = 2,203,342.22/2,145.72
6. Step 6: Final answer
   x = 1,026.85