Finding the Fourth Proportional to 3,871.35, 5,809.25 and 1,680.30

Step by Step Solution

1. Step 1: Write the proportion equation
   3,871.35 : 5,809.25 = 1,680.30 : x
2. Step 2: Convert to fraction form
   3,871.35/5,809.25 = 1,680.30/x
3. Step 3: Cross multiply
   3,871.35x = 5,809.25 × 1,680.30
4. Step 4: Simplify right side
   3,871.35x = 9,761,282.78
5. Step 5: Solve for x
   x = 9,761,282.78/3,871.35
6. Step 6: Final answer
   x = 2,521.42