Finding the Fourth Proportional to 11,388.83, 17,079.89 and 3,991.91

Step by Step Solution

1. Step 1: Write the proportion equation
   11,388.83 : 17,079.89 = 3,991.91 : x
2. Step 2: Convert to fraction form
   11,388.83/17,079.89 = 3,991.91/x
3. Step 3: Cross multiply
   11,388.83x = 17,079.89 × 3,991.91
4. Step 4: Simplify right side
   11,388.83x = 68,181,278.33
5. Step 5: Solve for x
   x = 68,181,278.33/11,388.83
6. Step 6: Final answer
   x = 5,986.68