Finding the Fourth Proportional to 11,128.05, 16,667.78 and 4,879.71

Step by Step Solution

1. Step 1: Write the proportion equation
   11,128.05 : 16,667.78 = 4,879.71 : x
2. Step 2: Convert to fraction form
   11,128.05/16,667.78 = 4,879.71/x
3. Step 3: Cross multiply
   11,128.05x = 16,667.78 × 4,879.71
4. Step 4: Simplify right side
   11,128.05x = 81,333,908.35
5. Step 5: Solve for x
   x = 81,333,908.35/11,128.05
6. Step 6: Final answer
   x = 7,308.91