At a certain school, twenty-five percent of the students wear a watch and thirty percent wear a bracelet. sixty percent of the students wear neither a watch nor a bracelet. (a) one of the students is chosen at random. what is the probability that this student is wearing a watch or a bracelet? (b) what is the probability that this student is wearing both a watch and a bracelet?

 a) 0.40    b) 0.15

Step-by-step explanation:

Let A denotes the event that students wear a watch and B denotes the event that students wear a bracelet.

Given : P(A)=0.25   ;   P(B)=0.30

Since,

Thus, the probability that this student is wearing a watch or a bracelet = 0.40

Also,

Thus,  the probability that this student is wearing both a watch and a bracelet= 0.15

45

step-by-step explanation: