Finding the Fourth Proportional to 1,443.90, 2,160.72 and 859.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.90 : 2,160.72 = 859.23 : x
2. Step 2: Convert to fraction form
   1,443.90/2,160.72 = 859.23/x
3. Step 3: Cross multiply
   1,443.90x = 2,160.72 × 859.23
4. Step 4: Simplify right side
   1,443.90x = 1,856,555.45
5. Step 5: Solve for x
   x = 1,856,555.45/1,443.90
6. Step 6: Final answer
   x = 1,285.79