Finding the Fourth Proportional to 13,728.34, 18,944.98 and 7,678.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,728.34 : 18,944.98 = 7,678.50 : x
2. Step 2: Convert to fraction form
   13,728.34/18,944.98 = 7,678.50/x
3. Step 3: Cross multiply
   13,728.34x = 18,944.98 × 7,678.50
4. Step 4: Simplify right side
   13,728.34x = 145,469,047.78
5. Step 5: Solve for x
   x = 145,469,047.78/13,728.34
6. Step 6: Final answer
   x = 10,596.26