Joshua and Jose work att an auto repair center with 4 other workers. For a survey on healthcare insurance, 2 of the 6 workers will be randomly chosen to be interviewd. What is the probability that Joshua and Jose both will be chosen?
1)1/15
2) 1/12
3)1/9
4)1/6
5) 1/3
The correct ans is A and i chose E can someone explain?
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Probability
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blue_lotus
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P = Number of favourable outcomes/ total outcomes
Total outcome = chosing 2 out of 6 = 6C2 = 15
Chosing 2 out of 2 = 2C2 = 1 . (There is only one way that both Joshua and Jose can be selected)
Therefore P = 1/15
Let me try to explain in another way to
Let Joseua= J, Jose = K others be b,c,d,e
Possible selections are jk,jb,jc,jd,je, kb,kc,kd,ke, bc,bd,be ,cd,ce , de = 15
Favourable outcome of both J and K being selected .Jk are together in the above sequence only once
Therefore P = 1/15
Total outcome = chosing 2 out of 6 = 6C2 = 15
Chosing 2 out of 2 = 2C2 = 1 . (There is only one way that both Joshua and Jose can be selected)
Therefore P = 1/15
Let me try to explain in another way to
Let Joseua= J, Jose = K others be b,c,d,e
Possible selections are jk,jb,jc,jd,je, kb,kc,kd,ke, bc,bd,be ,cd,ce , de = 15
Favourable outcome of both J and K being selected .Jk are together in the above sequence only once
Therefore P = 1/15
