Finding the Fourth Proportional to 2,859, 3,945.96 and 1,680.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,859 : 3,945.96 = 1,680.72 : x
2. Step 2: Convert to fraction form
   2,859/3,945.96 = 1,680.72/x
3. Step 3: Cross multiply
   2,859x = 3,945.96 × 1,680.72
4. Step 4: Simplify right side
   2,859x = 6,632,053.89
5. Step 5: Solve for x
   x = 6,632,053.89/2,859
6. Step 6: Final answer
   x = 2,319.71