Finding the Fourth Proportional to 3,912.80, 5,868.12 and 1,721

Step by Step Solution

1. Step 1: Write the proportion equation
   3,912.80 : 5,868.12 = 1,721 : x
2. Step 2: Convert to fraction form
   3,912.80/5,868.12 = 1,721/x
3. Step 3: Cross multiply
   3,912.80x = 5,868.12 × 1,721
4. Step 4: Simplify right side
   3,912.80x = 10,099,034.52
5. Step 5: Solve for x
   x = 10,099,034.52/3,912.80
6. Step 6: Final answer
   x = 2,581.02