Question 1. In a sample study of 640 people, it was found that 500 people go for yoga regularly in the morning.
(a) If a person is selected at random, then what is the probability that the person does not go for yoga exercise?
(b) Which mathematical concept is used in the above problem?
(c) By going for yoga, which value is depicted by the people?
Sol. (a) Since, the sample study is made on 640 people.
Number of people going for yoga regularly = 500
∴ Number of people who do not go for yoga = 640 – 500 = 140
⇒ Total possible outcomes = 640
Number of favourable outcomes = 140
∴ Probability of people who do not go for yoga = (140/640) = (7/32)
(b) Probability (c) Health awareness.
Question 2. In class IX, there are 40 students of whom 25 are girls and 15 are boys. They plan to spread awareness about water-management in different localities. Their class teacher has to select one student for the group representative. She writen the name of each student on a separate card, put them in a bag and stir thoroughly. She then, draws one card at random from the bag.
(a) What is the probability that the name written on the card is the name of a girl student?
(b) What is the probability that the name written on the card is the name of a boy student?
(c) Which mathematical concept is used in the above problem?
(d) By spreading awareness about water-management, which skill is depicted by the class IX students?
Sol. Number of girls = 25
Number of boys = 15
Total number of students = 25 + 15 =40
(a) Total number of outcomes = 40
Favourable number of outcomes = 25
⇒ Probability that the representative of the group is a girl-student
=(25/40) = (5/8)
(b) ä Total number of outcomes = 40
∴ Favourable number of outcomes = 15
⇒ Probability that the representative of the group is a boy-student
= (15/40) = (3/8)
(d) Proper use of natural resources.