Finding the Third Proportional to 3,986.50 and 8,728.75

Step by Step Solution

1. Step 1: Write the proportion equation
   3,986.50 : 8,728.75 = 8,728.75 : x
2. Step 2: Convert to fraction form
   3,986.50/8,728.75 = 8,728.75/x
3. Step 3: Cross multiply
   3,986.50x = 8,728.75 × 8,728.75
4. Step 4: Simplify right side
   3,986.50x = 76,191,076.56
5. Step 5: Solve for x
   x = 76,191,076.56/3,986.50
6. Step 6: Final answer
   x = 19,112.27