Finding the Third Proportional to 4,009.50 and 7,128

Step by Step Solution

1. Step 1: Write the proportion equation
   4,009.50 : 7,128 = 7,128 : x
2. Step 2: Convert to fraction form
   4,009.50/7,128 = 7,128/x
3. Step 3: Cross multiply
   4,009.50x = 7,128 × 7,128
4. Step 4: Simplify right side
   4,009.50x = 50,808,384
5. Step 5: Solve for x
   x = 50,808,384/4,009.50
6. Step 6: Final answer
   x = 12,672