initial quantity of tomato is 35
final quantity = 28
so the percentage change is,
[tex]=\frac{28-35}{35}\times100[/tex][tex]\begin{gathered} =\frac{-7}{35}\times100 \\ =-20\text{ \%} \end{gathered}[/tex]so the percentage change is -20%
the negative sign is showing the decrement in the quantity