Kelly has 45 cookies. she plans on bringing 2/3 of the cookies to school to share with her class. how many cookies will she not bringing to school?

If she is bringing 2/3 to school, then she is not bring 1/3

1/3 (45) = 45/3 = 15 ... so she is not bringing 15 cookies

or u can do it this way ...

she is bringing 2/3 ...

2/3 (45) = 90/3 = 30 ... she is bringing 30

45 - 30 = 15 ... not bringing 15.