Which of the operations +, -, * are inverse of each other

Abaker makes 186 cookies. some are chocolate chip and some are oatmeal raisin, and both kinds are made with and without nuts, as shown in the table above. because they are more popular, the baker made 2/3 of the cookies chocolate chip. if a chocolate chip cookie is chosen at random, what is the probability that it will have nuts? a) 21/93 b) 21/62 c) 41/93 d) 21/41

What is the length of the unknown leg in the right triangle ?

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u