Finding the Fourth Proportional to 3,947.40, 5,928.12 and 3,408.48

Step by Step Solution

1. Step 1: Write the proportion equation
   3,947.40 : 5,928.12 = 3,408.48 : x
2. Step 2: Convert to fraction form
   3,947.40/5,928.12 = 3,408.48/x
3. Step 3: Cross multiply
   3,947.40x = 5,928.12 × 3,408.48
4. Step 4: Simplify right side
   3,947.40x = 20,205,878.46
5. Step 5: Solve for x
   x = 20,205,878.46/3,947.40
6. Step 6: Final answer
   x = 5,118.78