. What are A and B = ?
A = {x|x > a} and B = {x|x > b}
A = {x|x < a} and B = {x|x > b}
A = {x|x < a} and B = {x|x < b}
A = {x|x > a} and B = {x|x < b}
The mean weight of 150 students in a certain class is 60 kg. The mean weight of boys is 70 kg and that of girls is 55 kg. What are the number of boys and girls respectively in the class?
75 and 75
50 and 100
70 and 80
100 and 50
What is the number of ways in which the letters of the word ‘ABLE’ can be arranged So that the Vowels occupy even places ?
2
4
6
8
B.
4
Consider word : ABLE
Vowels : A , E
Consonants : B, L
If vowels can take only even place then first fix vowels at even places.
Then consonants can be arranged in two ways :
1st place | 3rd place |
B | L |
L | B |
Also , these vowels can also be arranged in two ways.
Hence, Required Number of ways = 2 X 2 = 4