Finding the Fourth Proportional to 3,908.59, 5,393.86 and 2,116.09

Step by Step Solution

1. Step 1: Write the proportion equation
   3,908.59 : 5,393.86 = 2,116.09 : x
2. Step 2: Convert to fraction form
   3,908.59/5,393.86 = 2,116.09/x
3. Step 3: Cross multiply
   3,908.59x = 5,393.86 × 2,116.09
4. Step 4: Simplify right side
   3,908.59x = 11,413,884.50
5. Step 5: Solve for x
   x = 11,413,884.50/3,908.59
6. Step 6: Final answer
   x = 2,920.21