Answer :
[tex]\frac{2}{5} \ of \ 128= \frac{2}{5}*128= \\\\ = 2* 25.6= \\\\ =\boxed{51.2}[/tex]
2/5 of 128
of means multiplication so
2/5 x 128=
2/5 x 128/1
256/5 would be the answer but you have to divide
256/5= 51.2
so the answer to 2/5 of 128 would be 51.2