Chapter 7
The Mathematics of Maybe: Introduction to Probability
CBSE Class 9
Mathematics Solutions
Educart Mathematics class Class 9 NCERT Exemplar cover
Question:

A survey is conducted at a school where a random sample of 40 students is asked about their favourite club. The responses are:
14 students: Science Club
11 students: Arts Club
9 students: Sports Club
6 students: Debate Club
Assume there are 800 students in the whole school.

(A) What is the probability that a randomly chosen student from the sample prefers the Arts Club?

(B) Using the sample results, estimate how many students in the whole school are likely to prefer the Sports Club.                                                                                                                                                                                                              [Page No. 165]

Answer: Verified

Given,

Total students = 40

(A) P(Arts Club)=1140P(\text{Arts Club}) = \frac{11}{40}

(B) P(Sports Club)=940P(\text{Sports Club}) = \frac{9}{40}

Estimated number of students who prefer a sports club in the whole school
                                                                  = 940×800\frac{9}{40} \times 800

=9×20=180 students.= 9 \times 20 = 180 \text{ students.}

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More NCERT Questions
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