Finding the Fourth Proportional to 11,389.82, 17,078.34 and 3,991.38

Step by Step Solution

1. Step 1: Write the proportion equation
   11,389.82 : 17,078.34 = 3,991.38 : x
2. Step 2: Convert to fraction form
   11,389.82/17,078.34 = 3,991.38/x
3. Step 3: Cross multiply
   11,389.82x = 17,078.34 × 3,991.38
4. Step 4: Simplify right side
   11,389.82x = 68,166,095.63
5. Step 5: Solve for x
   x = 68,166,095.63/11,389.82
6. Step 6: Final answer
   x = 5,984.83