Finding the Fourth Proportional to 13,632.78, 18,808.83 and 8,920.20

Step by Step Solution

1. Step 1: Write the proportion equation
   13,632.78 : 18,808.83 = 8,920.20 : x
2. Step 2: Convert to fraction form
   13,632.78/18,808.83 = 8,920.20/x
3. Step 3: Cross multiply
   13,632.78x = 18,808.83 × 8,920.20
4. Step 4: Simplify right side
   13,632.78x = 167,778,525.37
5. Step 5: Solve for x
   x = 167,778,525.37/13,632.78
6. Step 6: Final answer
   x = 12,306.99