Finding the Fourth Proportional to 12,873.72, 17,768.50 and 7,839.60

Step by Step Solution

1. Step 1: Write the proportion equation
   12,873.72 : 17,768.50 = 7,839.60 : x
2. Step 2: Convert to fraction form
   12,873.72/17,768.50 = 7,839.60/x
3. Step 3: Cross multiply
   12,873.72x = 17,768.50 × 7,839.60
4. Step 4: Simplify right side
   12,873.72x = 139,297,932.60
5. Step 5: Solve for x
   x = 139,297,932.60/12,873.72
6. Step 6: Final answer
   x = 10,820.33