DS: of the people who

[Khush]

Of the people who attended a workshop, 60 percent were teachers and some of the teachers were teachers of language arts. What percent of the people who attended the workshop were teachers of language arts?

(1) 200 people attended the workshop.

(2) 72 of the teachers who attended the workshop were not teachers of language arts.

i am not able to solve this question by using the matrix method. please help.

[RonPurewal]

please post some more specifics about the issue(s) you're having with the problem.

what did you do with your matrix for each statement?
what did you understand?
what didn't you understand?
etc.

thanks.

[Khush]

Hi RON.
i think i wrongly put the values in the matrix.

As the correct answer is C, i must have made a mistake in understanding the data.

I assigned values as below:

T and L -> the value is asked in the question
T= 0.6x
~T= 0.4x
~L and ~T = (72*0.6 x)

where x= total number of people attending the workshop
T= number of teachers
~T= NO teachers
L= number of language arts workshop attendees
~L= NO language arts attendees

i think i did not get which data belong to which box. i usually solve such questions with ease, using double matrix. don't know why find this one little confusing.

[RonPurewal]

if you're using the two statements together, there is no reason to use a variable.
• the total number of teachers is %60 of 200 ––> 120 teachers.
• 72 of these teachers did NOT teach language arts.
• so, (120 - 72) of them did.
if you make the matrix, these three numbers should be in a single row or column.

then, since the problem wants a percentage, you can divide by 200, and you'll have one.

[RonPurewal]

as far as takeaways here--

it's quite clear that you don't need a variable here (when you use the statements together).
so, i'm guessing, you must have just tossed a variable in there BEFORE looking over the information you have.
if so ... bad idea.

• don't define variables unless you NEED them.

• read through ALL given information before deciding whether you need a variable.

[Khush]

Thank You Ron!
got it.

[RonPurewal]

you're welcome.