Finding the Fourth Proportional to 2,321.72, 3,479.88 and 859.94

Step by Step Solution

1. Step 1: Write the proportion equation
   2,321.72 : 3,479.88 = 859.94 : x
2. Step 2: Convert to fraction form
   2,321.72/3,479.88 = 859.94/x
3. Step 3: Cross multiply
   2,321.72x = 3,479.88 × 859.94
4. Step 4: Simplify right side
   2,321.72x = 2,992,488.01
5. Step 5: Solve for x
   x = 2,992,488.01/2,321.72
6. Step 6: Final answer
   x = 1,288.91