Finding the Fourth Proportional to 1,708.28, 2,560.72 and 721.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,708.28 : 2,560.72 = 721.34 : x
2. Step 2: Convert to fraction form
   1,708.28/2,560.72 = 721.34/x
3. Step 3: Cross multiply
   1,708.28x = 2,560.72 × 721.34
4. Step 4: Simplify right side
   1,708.28x = 1,847,149.76
5. Step 5: Solve for x
   x = 1,847,149.76/1,708.28
6. Step 6: Final answer
   x = 1,081.29