Given: A dice is thrown once
Required to find:
(i) Probability of getting a prime number
(ii) Probability of getting 2 or 4
(iii) Probability of getting a multiple of 2 or 3.
(iv) Probability of getting an even number
(v) Probability of getting a number greater than five.
(vi) Probability of lying between 2 and 6
Total number on a dice is 6 i.e., 1, 2, 3, 4, 5 and 6.
(i) Prime numbers on a dice are 2, 3, and 5. So, the total number of prime numbers is 3.
We know that, Probability = Number of favourable outcomes/ Total number of outcomes
Thus, probability of getting a prime number =
3
6
3
=
1
2
1
(ii) For getting 2 and 4, clearly the number of favourable outcomes is 2.
We know that Probability = Number of favourable outcomes/ Total number of outcomes
Thus, the probability of getting 2 or 4 =
2
6
2
=
1
3
1
(iii) Multiple of 2 are 3 are 2, 3, 4 and 6.
So, the number of favourable outcomes is 4
We know that, Probability = Number of favourable outcomes/ Total number of outcomes
Thus, the probability of getting an multiple of 2 or 3 =
4
6
4
=
2
3
2
(iv) An even prime number is 2 only.
So, the number of favourable outcomes is 1.
We know that, Probability = Number of favourable outcomes/ Total number of outcomes
Thus, the probability of getting an even prime number =
1
6
1
(v) A number greater than 5 is 6 only.
So, the number of favourable outcomes is 1.
We know that, Probability = Number of favourable outcomes/ Total number of outcomes
Thus, the probability of getting a number greater than 5 =
1
6
1
(vi) Total number on a dice is 6.
Numbers lying between 2 and 6 are 3, 4 and 5
So, the total number of numbers lying between 2 and 6 is 3.
We know that, Probability = Number of favourable outcomes/ Total number of outcomes
Thus, the probability of getting a number lying between 2 and 6 =
3
6
3
=
1
2
1
