# Which of the following arguments are correct and which are not correct? Give reasons for your answer.

(i) If two coins are tossed simultaneously there are three possible outcomes—two heads, two tails or one of each. Therefore, for each of these outcomes, the probability is 1/3

(ii) If a die is thrown, there are two possible outcomes—an odd number or an even number. Therefore, the probability of getting an odd number is 1/2

**Solution:**

We use the basic concepts of probability to find the required outcomes.

(i) Incorrect

If two coins are tossed simultaneously then,

Total possible outcomes are (H, H), (T, T), (H, T), (T, H) = 4

Number of outcomes to get two heads = (H, H) = 1

Number of outcomes to get two tails = (T, T) = 1

Number of outcomes to get any one of each = (H, T), (T, H) = 2

probability of getting two heads = Number of possible outcomes/Total number of favourable outcomes

= 1/4

probability of getting two tails = Number of possible outcomes/Total number of favourable outcomes

= 1/4

probability of getting one of each = Number of possible outcomes/Total number of favourable outcomes

= 2/4 = 1/2

It can be observed that the probability of each of the outcomes is not 1/3.

(ii) Correct

Total number of possible outcomes when a die is thrown = (1, 2, 3, 4, 5, 6)

Number of possible outcomes to get an odd number (1, 3, 5) = 3

Number of possible outcomes to get an even number (2, 4, 6) = 3

probability of getting odd number = Number of possible outcomes/Number of favourable outcomes

= 3/6 = 1/2

Thus, the probability of getting an odd number is 1/2.

Check out more about terms of probability.

**☛ Check: **NCERT Solutions for Class 10 Maths Chapter 15

**Video Solution:**

## Which of the following arguments are correct and which are not correct? Give reasons for your answer. (i) If two coins are tossed simultaneously there are three possible outcomes—two heads, two tails or one of each. Therefore, for each of these outcomes, the probability is 1/3 (ii) If a die is thrown, there are two possible outcomes—an odd number or an even number. Therefore, the probability of getting an odd number is 1/2.

NCERT Solutions for Class 10 Maths Chapter 15 Exercise 15.1 Question 25

**Summary:**

The argument (i) If two coins are tossed simultaneously there are three possible outcomes—two heads, two tails or one of each. Therefore, for each of these outcomes, the probability is 1/3 is incorrect and the argument (ii) If a die is thrown, there are two possible outcomes—an odd number or an even number. Therefore, the probability of getting an odd number is 1/2.is correct

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