Answer :
In the present question, it is required to calculate 7/8 of 160, because it is the number of magazines sold yesterday.
From this, we perform the calculation as follows:
[tex]\begin{gathered} \frac{1}{8}of\text{ }160=\frac{160}{8}=20 \\ \frac{7}{8}of160=7\times\frac{1}{8}\text{ of }160=7\times20=140 \end{gathered}[/tex]From the solution presented above, we are able to conclude that the number of copies sold yesterday was 140.