Finding the Fourth Proportional to 2,108.39, 3,162.17 and 721.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,108.39 : 3,162.17 = 721.61 : x
2. Step 2: Convert to fraction form
   2,108.39/3,162.17 = 721.61/x
3. Step 3: Cross multiply
   2,108.39x = 3,162.17 × 721.61
4. Step 4: Simplify right side
   2,108.39x = 2,281,834.07
5. Step 5: Solve for x
   x = 2,281,834.07/2,108.39
6. Step 6: Final answer
   x = 1,082.27