The Venn diagram is given below. Then the number of students who have brother and sister will be 6.
A set is a group of clearly specified components. The number of items in a finite set is denoted by a curly bracket.
In a class of 20 students:
11 have a brother, 9 have a sister, and 6 have neither.
Then the Venn diagram will be
11 – a + a + 9 – a = 20 – 6
20 – a = 14
a = 6
The Venn diagram is given below.
More about the sets link is given below.
https://brainly.com/question/8053622
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