Answer: There are 18 scarves which he can make.
Step-by-step explanation:
Since we have given that
Number of balls Christopher bought = 12
From \(\dfrac{2}{3}\) of a ball, he can make 1 scarf.
So, from 12 balls , number of scarves he can make is given by
\(\dfrac{\text{Number of balls }}{\text{Number of balls to make 1 scarf}}\\\\=\dfrac{12}{\dfrac{2}{3}}\\\\\\=\dfrac{12\times 3}{2}\\\\=\dfrac{36}{2}\\\\=18\)
Hence, there are 18 scarves which he can make.