All the students of a class performed poorly in Mathematics. The teacher
decided to give grace marks of $10$ to each of the students. Which of the
following statistical measures will not change even after the grace marks were
given?
At present, a firm is manufacturing $2000$ items. It is estimated that the rate of
change of production $P$ w.r.t. additional number of workers $x$ is given by
$\dfrac{dP}{dx}=100-12\sqrt{x}$. If the firm employs $25$ more workers, then the
new level of production of items is :
Statement-1 : The value of the integral
$\displaystyle \int_{\pi/6}^{\pi/3}\frac{dx}{1+\sqrt{\tan x}}$ is equal to $\pi/6$
Statement-2 : $\displaystyle \int_{a}^{b}f(x)\,dx=\int_{a}^{b}f(a+b-x)\,dx$.
Let $T_{n}$ be the number of all possible triangles formed by joining vertices
of an $n$-sided regular polygon. If $T_{n+1}-T_{n}=10$, then the value of $n$ is :
The number of values of $k$, for which the system of equations : $\matrix{
{\left( {k + 1} \right)x + 8y = 4k} \cr
{kx + \left( {k + 3} \right)y = 3k - 1} \cr
} $
If the vectors $\overrightarrow {AB} = 3\widehat i + 4\widehat k$ and $\overrightarrow {AC} = 5\widehat i - 2\widehat j + 4\widehat k$ are the sides of a triangle $ABC,$ then the length of the median through $A$ is :