In a survey of 300 companies, the number of companies using different Media-Newspapers N(N), Radio (R) and Television (T) are as follows: $\displaystyle N(N) = 200$, $\displaystyle N(R) = 100$, $\displaystyle N(T) = 40$, $\displaystyle N(N \cap R) = 20$, $\displaystyle N(R \cap T) = 20$, $\displaystyle N(N \cap T) = 30$ and $\displaystyle N(N \cap R \cap T) = 5$. Find the numbers of companies using none of these media:

If $\displaystyle A = \{1, 2, 3, 4, 5\}$, $\displaystyle B = \{2, 4\}$ and $\displaystyle C = \{1, 3, 5\}$ then $\displaystyle (A - C)$$\displaystyle \times$ B is:

If $\displaystyle f(x)=x^2-5$, evaluate $\displaystyle f(3)$, $\displaystyle f(-4)$, $\displaystyle f(5)$, and $\displaystyle f(1)$.

Out of a group of $20$ teachers in a school, $10$ teach Mathematics, $\displaystyle 9$ teach Physics and $\displaystyle 7$ teach Chemistry. $\displaystyle 4$ teach Mathematics and Physics but none teach both Mathematics and Chemistry. How many teach Chemistry and Physics; how many teach only Physics?

If $\displaystyle A = \{1, 2, 3, 4, 5, 7, 8, 9\}$ and $\displaystyle B = \{2, 4, 6, 7, 9\}$ then how many proper subset of $\displaystyle A \cap B$ can be created?

The number of subsets of the set $\displaystyle \{0, 1, 2, 3\}$ is:

If $\displaystyle f(x) = x^2+x-1$ and $4f(x) = f(2x)$, then find the value of 'x'.