200 elementary school students were surveyed to find their blood groups. Of those, 55 were of blood group A, 85 of blood group B, and 21 of blood group O.

What is the probability that a randomly chosen student has either blood group A or blood group B?

What is the fewest number of full weeks briyana would have to work to have enough money? 8 weeks9 weeks 10 weeks11 weeks

Exercise: counting committees 0.0/2.0 puntos (calificable) we start with a pool of n people. a chaired committee consists of k≥1 members, out of whom one member is designated as the chairperson. the expression k(nk) can be interpreted as the number of possible chaired committees with k members. this is because we have (nk) choices for the k members, and once the members are chosen, there are then k choices for the chairperson. thus, c=∑k=1nk(nk) is the total number of possible chaired committees of any size. find the value of c (as a function of n ) by thinking about a different way of forming a chaired committee: first choose the chairperson, then choose the other members of the committee. the answer is of the form c=(α+nβ)2γn+δ. what are the values of α , β , γ , and δ ?

The graph of f(x) = x is reflected over the y-axis. use the graphing calculator to graph this reflection. which list containsthree points that lie on the graph of the reflection?