Finding the Fourth Proportional to 12,789.31, 19,186.59 and 5,393.77

Step by Step Solution

1. Step 1: Write the proportion equation
   12,789.31 : 19,186.59 = 5,393.77 : x
2. Step 2: Convert to fraction form
   12,789.31/19,186.59 = 5,393.77/x
3. Step 3: Cross multiply
   12,789.31x = 19,186.59 × 5,393.77
4. Step 4: Simplify right side
   12,789.31x = 103,488,053.54
5. Step 5: Solve for x
   x = 103,488,053.54/12,789.31
6. Step 6: Final answer
   x = 8,091.76