Finding the Fourth Proportional to 10,919.88, 16,379.99 and 3,128.69

Step by Step Solution

1. Step 1: Write the proportion equation
   10,919.88 : 16,379.99 = 3,128.69 : x
2. Step 2: Convert to fraction form
   10,919.88/16,379.99 = 3,128.69/x
3. Step 3: Cross multiply
   10,919.88x = 16,379.99 × 3,128.69
4. Step 4: Simplify right side
   10,919.88x = 51,247,947.95
5. Step 5: Solve for x
   x = 51,247,947.95/10,919.88
6. Step 6: Final answer
   x = 4,693.09