In a class,30 offer Biology,21 offer Chemistry and 22 offer Physics.15 offer Physics and Biology,10 offer Physics and Chemistry and 13 offer Biology and Chemistry.2 offer Physics only,3 offer Chemistry only and 7 offer Biology only.
a.illustrate this information in a Venn diagram
b.find the number of students
i.who offer all the three subjects
ii.in the class
C.If a student is selected at random, what is the probability that he studies either Physics or Chemistry.
In a class,30 offer biology,21 offer are chemistry and 22 offer are physics.15 offer physics and biology,10 offer physics and chemistry and 13 offer biology and chemistry,2 offer physics only,5 offer chemistry only,and 7 offer biology only.(I)illustrate this information in a Venn diagram.(ii)find the number of students.(a)who offer all the three subjects.(b)in the class.(c)if a student s sellected at random what is the probability that is studies either physics or chemistry.
is the person answering the question above?
draw the Venn diagram. It is easy to fill in
2 offer Physics only,3 offer Chemistry only and 7 offer Biology only.
Now if we let
x = only Biology and Chemistry
y = only Biology and Physics
z = only Chemistry and physics
a = all three
Then we have
x+y+7+a = 30
x+z+3+a = 21
y+z+2+a = 22
There is no unique solution, since we do not know how many students there are in the class. But the above equations tell us that
y = x+2 = z+5
So some solutions are
x y z a Class
4 6 1 13 36
5 7 2 11 37
...
10 12 7 1 42
I wants my answer
Yes
I am not get the right answer
ii) 25
b) 12
I) 98