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The probability that the first student chosen is a senior and the second student chosen is a sophomore is 11/320.
What is probability?
Probability of an event is the ratio of number of favorable outcome to the total number of outcome of that event.
Twice during the assembly, a student is chosen at random to assist with the presentation.
After the first student has finished assisting, the student returns to the group and can be chosen a second time.
There are total 80 number of students in which 22 are senior students. Thus, probability of choosing first student a senior
[tex]P(A)=\dfrac{22}{80}\\P(A)=\dfrac{11}{40}[/tex]
There are total 22 sophomores. Thus, probability of choosing second student a sophomore is,
[tex]P(B)=\dfrac{10}{80}\\P(B)=\dfrac{1}{8}[/tex]
By the chain rule, the probability that the first student chosen is a senior and the second student chosen is a sophomore is
[tex]\dfrac{11}{8}\times \dfrac{1}{8}=\dfrac{11}{320}[/tex]
Thus, the probability that the first student chosen is a senior and the second student chosen is a sophomore is 11/320.
Learn more about the probability here;
https://brainly.com/question/24756209
