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4 years ago

7

At a DBE lecture of 100 students, there are 29 women and 23 men. Out of these students, 4 are teachers and 24 are either men or

teachers. Find the number of women teachers attending the lecture?

1 answer:

den301095 [7]4 years ago

5 0

Answer:

The number of women teachers attending the lecture is 1.

Step-by-step explanation:

Denote the variables as follows:

<em>M</em> = men

<em>W</em> = women

<em>T</em> = teacher

The data provided is:

n (M) = 23

n (W) = 29

n (T) = 4

n (M ∪ T) = 24

Compute the number of men teachers as follows:

$n(M\cap T)=n(M)+n(T)-n(M\cup T)$

$=23+4-24\\=3$

Compute the number of women teachers as follows:

$n(T)=n(M\cap T)+n(W\cap T)$

$4=3+n(W\cap T)$

$n(W\cap T)=1$

Thus, the number of women teachers attending the lecture is 1.

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