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In a class of 30 learners, five take Maths, Geography and Biology. Nine take Maths and Biology. Twenty learners take Geography, of whom twelve also take Maths.Eighteen take Biology. Every learner takes at least one subject, and no one takes only Maths. How many learners take only Biology?
1) One. Ref - "Nine take Maths and Biology." I assumed they wouldn't take Geography.
2)Six. Ref - "Nine take Maths and Biology." Assuming these 9 are free to take up Geography.
"Nine take Maths and Biology." - Just by reading this statement, one can't judge if these nine can take up Geography or not. Can you?
6 takes only biology..
You are right Barbie. Give us your solution.
5 - take up maths, geography, biology 7 - take maths and geography alone 4 - take maths and biology alone now, total number of biology learners, 18. Total number of geography students , 20. (12 -take up maths too, hence 8 remain) total number of students=30 remaining sudents (these are bio alone students) = 30-8-12-4 = 6
Yeah. Thats the right solution. I don know how to explain that one.
So i tried to uploaded a image file for the solution. but it shows some errors.
Even I got the solution using Venn Diagram.