Finding the Fourth Proportional to 6,911.72, 9,538.42 and 3,928.05

Step by Step Solution

1. Step 1: Write the proportion equation
   6,911.72 : 9,538.42 = 3,928.05 : x
2. Step 2: Convert to fraction form
   6,911.72/9,538.42 = 3,928.05/x
3. Step 3: Cross multiply
   6,911.72x = 9,538.42 × 3,928.05
4. Step 4: Simplify right side
   6,911.72x = 37,467,390.68
5. Step 5: Solve for x
   x = 37,467,390.68/6,911.72
6. Step 6: Final answer
   x = 5,420.85