Finding the Fourth Proportional to 3,912.78, 5,870.58 and 1,721.25

Step by Step Solution

1. Step 1: Write the proportion equation
   3,912.78 : 5,870.58 = 1,721.25 : x
2. Step 2: Convert to fraction form
   3,912.78/5,870.58 = 1,721.25/x
3. Step 3: Cross multiply
   3,912.78x = 5,870.58 × 1,721.25
4. Step 4: Simplify right side
   3,912.78x = 10,104,735.83
5. Step 5: Solve for x
   x = 10,104,735.83/3,912.78
6. Step 6: Final answer
   x = 2,582.50