Finding the Fourth Proportional to 2,157.29, 3,229.49 and 1,321.73

Step by Step Solution

1. Step 1: Write the proportion equation
   2,157.29 : 3,229.49 = 1,321.73 : x
2. Step 2: Convert to fraction form
   2,157.29/3,229.49 = 1,321.73/x
3. Step 3: Cross multiply
   2,157.29x = 3,229.49 × 1,321.73
4. Step 4: Simplify right side
   2,157.29x = 4,268,513.82
5. Step 5: Solve for x
   x = 4,268,513.82/2,157.29
6. Step 6: Final answer
   x = 1,978.65