Finding the Fourth Proportional to 3,989.04, 5,982.12 and 1,680.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,989.04 : 5,982.12 = 1,680.72 : x
2. Step 2: Convert to fraction form
   3,989.04/5,982.12 = 1,680.72/x
3. Step 3: Cross multiply
   3,989.04x = 5,982.12 × 1,680.72
4. Step 4: Simplify right side
   3,989.04x = 10,054,268.73
5. Step 5: Solve for x
   x = 10,054,268.73/3,989.04
6. Step 6: Final answer
   x = 2,520.47