Finding the Fourth Proportional to 3,926.72, 5,890.35 and 1,328.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,926.72 : 5,890.35 = 1,328.78 : x
2. Step 2: Convert to fraction form
   3,926.72/5,890.35 = 1,328.78/x
3. Step 3: Cross multiply
   3,926.72x = 5,890.35 × 1,328.78
4. Step 4: Simplify right side
   3,926.72x = 7,826,979.27
5. Step 5: Solve for x
   x = 7,826,979.27/3,926.72
6. Step 6: Final answer
   x = 1,993.26