Finding the Fourth Proportional to 5,721.83, 7,890.98 and 3,928.49

Step by Step Solution

1. Step 1: Write the proportion equation
   5,721.83 : 7,890.98 = 3,928.49 : x
2. Step 2: Convert to fraction form
   5,721.83/7,890.98 = 3,928.49/x
3. Step 3: Cross multiply
   5,721.83x = 7,890.98 × 3,928.49
4. Step 4: Simplify right side
   5,721.83x = 30,999,636.02
5. Step 5: Solve for x
   x = 30,999,636.02/5,721.83
6. Step 6: Final answer
   x = 5,417.78