Finding the Fourth Proportional to 13,290.57, 19,932.62 and 3,928.05

Step by Step Solution

1. Step 1: Write the proportion equation
   13,290.57 : 19,932.62 = 3,928.05 : x
2. Step 2: Convert to fraction form
   13,290.57/19,932.62 = 3,928.05/x
3. Step 3: Cross multiply
   13,290.57x = 19,932.62 × 3,928.05
4. Step 4: Simplify right side
   13,290.57x = 78,296,308.35
5. Step 5: Solve for x
   x = 78,296,308.35/13,290.57
6. Step 6: Final answer
   x = 5,891.12