Finding the Fourth Proportional to 9,900.45, 13,661.33 and 5,920.11

Step by Step Solution

1. Step 1: Write the proportion equation
   9,900.45 : 13,661.33 = 5,920.11 : x
2. Step 2: Convert to fraction form
   9,900.45/13,661.33 = 5,920.11/x
3. Step 3: Cross multiply
   9,900.45x = 13,661.33 × 5,920.11
4. Step 4: Simplify right side
   9,900.45x = 80,876,546.75
5. Step 5: Solve for x
   x = 80,876,546.75/9,900.45
6. Step 6: Final answer
   x = 8,168.98