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 = 15so 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 = 15not bringing 15.