probability
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A dance instructor conducts annual workshops in which he holds sessions for basic learners and trainers. In a particular year, 2000 people attended the workshop. 1500 participated as learners and 800 as trainers. How many participated as only trainers?
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Hi,
Probability ???? Ain't it Set theory ?!?!?
n (A) = 1500
n (B) = 800
n (A union B) = 2000
n (A union B) = n(A) + n(B) - n(A intersection B)
2000 = 1500 + 800 - x
Hence, x = 300. i.e., 300 ppl were both trainers and learners.
Hence, only trainers = [spoiler]800 - 300 = 500[/spoiler].
Hope this helps. Thanks.
Probability ???? Ain't it Set theory ?!?!?
n (A) = 1500
n (B) = 800
n (A union B) = 2000
n (A union B) = n(A) + n(B) - n(A intersection B)
2000 = 1500 + 800 - x
Hence, x = 300. i.e., 300 ppl were both trainers and learners.
Hence, only trainers = [spoiler]800 - 300 = 500[/spoiler].
Hope this helps. Thanks.
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai