Let $A = \{1, 2, 3, 4, 5, 6, 7\}$ and $B = \{3, 6, 7, 9\}$. Then the number of elements in the set $\{ C \subseteq A : C \cap B \neq \phi \}$ is

$A$ survey shows that $73 \%$ of the persons working in an office like coffee,whereas $65 \%$ like tea. If $x$ denotes the percentage of them who like both coffee and tea,then $x$ cannot be

In a certain examination,a candidate has to pass in each of the $5$ subjects. The number of ways in which the candidate can fail is:

In a group of students,$100$ students know Hindi,$50$ know English,and $25$ know both. Each student knows either Hindi or English. How many students are there in the group?

In a city,$20\%$ of the population travels by car,$50\%$ travels by bus,and $10\%$ travels by both car and bus. Then,the percentage of persons travelling by car or bus is......$\%$

In a class of $60$ students, $40$ opted for $NCC$, $30$ opted for $NSS$, and $20$ opted for both $NCC$ and $NSS$. If one of these students is selected at random, then the probability that the selected student has opted for neither $NCC$ nor $NSS$ is