Finding the Fourth Proportional to 10,086.80, 13,920.09 and 5,611.10

Step by Step Solution

1. Step 1: Write the proportion equation
   10,086.80 : 13,920.09 = 5,611.10 : x
2. Step 2: Convert to fraction form
   10,086.80/13,920.09 = 5,611.10/x
3. Step 3: Cross multiply
   10,086.80x = 13,920.09 × 5,611.10
4. Step 4: Simplify right side
   10,086.80x = 78,107,017.00
5. Step 5: Solve for x
   x = 78,107,017.00/10,086.80
6. Step 6: Final answer
   x = 7,743.49