MGMAT-no. of students in the orchestra only

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All of the students of Music High School are in the band, the orchestra, or both. 80 percent of the students are in only one group. There are 119 students in the band. If 50 percent of the students are in the band only, how many students are in the orchestra only?

30

51

60

85

119
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by goyalsau » Tue Sep 14, 2010 1:30 pm
alivapriyada wrote:All of the students of Music High School are in the band, the orchestra, or both. 80 percent of the students are in only one group. There are 119 students in the band. If 50 percent of the students are in the band only, how many students are in the orchestra only?

30

51

60

85

119
I think its 51.

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by diebeatsthegmat » Tue Sep 14, 2010 7:54 pm
goyalsau wrote:
alivapriyada wrote:All of the students of Music High School are in the band, the orchestra, or both. 80 percent of the students are in only one group. There are 119 students in the band. If 50 percent of the students are in the band only, how many students are in the orchestra only?

30

51

60

85

119
I think its 51.
you should write the solution instead of just saying the right answer because i think she knows it. the thing she wants to know is how to get 51, the right answer

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by diebeatsthegmat » Tue Sep 14, 2010 7:59 pm
alivapriyada wrote:All of the students of Music High School are in the band, the orchestra, or both. 80 percent of the students are in only one group. There are 119 students in the band. If 50 percent of the students are in the band only, how many students are in the orchestra only?

30

51

60

85

119
you know that 80% just in one group thus there is 20% in both group ( orchestra and band)
50% in only band thus 30% in only orchestra. now we have to find the number of students in only orchestra
119 student in band which includes 50% students in only band and 20% in both
thus we will get 70%
supposed x is the student in the school/group
thus 70%x=119 so x=170
30%*170=51
the correct answer is B

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by alivapriyada » Tue Sep 14, 2010 11:17 pm
diebeatsthegmat wrote:
alivapriyada wrote:All of the students of Music High School are in the band, the orchestra, or both. 80 percent of the students are in only one group. There are 119 students in the band. If 50 percent of the students are in the band only, how many students are in the orchestra only?

30

51

60

85

119
you know that 80% just in one group thus there is 20% in both group ( orchestra and band)
50% in only band thus 30% in only orchestra. now we have to find the number of students in only orchestra
119 student in band which includes 50% students in only band and 20% in both
thus we will get 70%
supposed x is the student in the school/group
thus 70%x=119 so x=170
30%*170=51
the correct answer is B
thanks for a detailed explanation