Tag: maths

Questions Related to maths

Mid point of $A(0, 0)$ and $B(1024, 2050)$ is ${A _1}$. mid point of ${A _1}$ and B is ${A _2}$ and so on. Coordinates of ${A _{10}}$ are.

  1. $(1022, 2044)$

  2. $(1025, 2050)$

  3. $(1023, 2046)$

  4. $(1, 2)$


Correct Option: C

If the coordinates of the extermities of diagonal of a square are $(2,-1)$ and $(6,2)$, then the coordinates of extremities of other diagonal are 

  1. $\left(\dfrac{5}{2},\dfrac{5}{2}\right)$

  2. $\left(\dfrac{11}{2},\dfrac{3}{2}\right)$

  3. $\left(\dfrac{11}{2},\dfrac{-3}{2}\right)$

  4. $\left(\dfrac{5}{2},-\dfrac{5}{2}\right)$


Correct Option: C
Explanation:

$\begin{array}{l} Coordination\, \, of\, \, mid-po{ { int } }\, \, 0 \ =\left( { \frac { { 6+2 } }{ 2 } ,\frac { { 2-1 } }{ 2 }  } \right)  \ =\left( { 4,\frac { 1 }{ 2 }  } \right)  \ AB=BC \ \Rightarrow { \left( { { x _{ 1 } }-2 } \right) ^{ 2 } }+{ \left( { { y _{ 1 } }+1 } \right) ^{ 2 } }={ \left( { { x _{ 1 } }-6 } \right) ^{ 2 } }+{ \left( { { y _{ 1 } }-2 } \right) ^{ 2 } } \ \Rightarrow 8{ x _{ 1 } }+6{ y _{ 1 } }=35\to (i) \ AO=BO \ \Rightarrow { \left( { 2-4 } \right) ^{ 2 } }+{ \left( { -1-\frac { 1 }{ 2 }  } \right) ^{ 2 } }={ \left( { { x _{ 1 } }-4 } \right) ^{ 2 } }+{ \left( { { y _{ 1 } }-\frac { 1 }{ 2 }  } \right) ^{ 2 } } \ \Rightarrow 4+\frac { 9 }{ 4 } =x _{ _{ 1 } }^{ 2 }+y _{ 1 }^{ 2 }-8{ x _{ 1 } }-{ y _{ 1 } }+16+\frac { 1 }{ 4 }  \ \Rightarrow x _{ 1 }^{ 2 }+y _{ 1 }^{ 2 }-8{ x _{ 1 } }-{ y _{ 1 } }=-10\to (ii) \ from\, \, equation\, \, (i) \ put \ { x _{ 1 } }=\frac { { 35-6{ y _{ 1 } } } }{ 8 } \, \, in\, \, equation\, \, (ii) \ \Rightarrow { \left( { \frac { { 35-6{ y _{ 1 } } } }{ 8 }  } \right) ^{ 2 } }+y _{ 1 }^{ 2 }-\left( { 35-6{ y _{ 1 } } } \right) { y _{ 1 } }=-10 \ \Rightarrow 4y _{ 1 }^{ 2 }-4{ y _{ 1 } }-15=0 \ \Rightarrow \left( { 2{ y _{ 1 } }+3 } \right) \left( { { y _{ 1 } }-5 } \right) =0 \ \Rightarrow { y _{ 1 } }=\frac { { -3 } }{ 2 } ,5 \ { y _{ 1 } }=\frac { { -3 } }{ 2 } \to { x _{ 1 } }=\frac { { 35-6\times -\frac { 3 }{ 2 }  } }{ 8 } =\frac { { 11 } }{ 2 }  \ { y _{ 1 } }=5\to { x _{ 1 } }=\frac { { 35-6\times 5 } }{ 8 } =\frac { 5 }{ 8 }  \ The\, \, vertices\, of\, \, other\, \, two\, vertices\, \, are \ \left( { \frac { { 11 } }{ 2 } ,\frac { { -3 } }{ 2 }  } \right) \, \, and\, \, \left( { \frac { 5 }{ 8 } ,5 } \right)  \end{array}$

O is a point that lies in the interior of $\Delta ABC$. Then $2(OA - OB -OC) > \text{Perimeter}\ of\ \Delta ABC$.

  1. True

  2. False


Correct Option: B
Explanation:
From the $\triangle ABC,$ by triangle inequality,
$ OA+OB>AB$ ....... $(i)$
$ OB+OC>BC$ ........ $(ii)$
$ OA+OC>AC$ ........ $(iii)$
By adding $(i),(ii)$ and $(iii)$
$ 2(OA+OB+OC)>AB+BC+AC$
$ \therefore 2(OA+OB+OC)>\text{Perimeter of triangle } ABC$
Hence, the statement is false.

Sum of the length of any two sides of a triangle is always greater than the length of third side.

  1. True

  2. False


Correct Option: A
$\dfrac{\sin 2x}{2\cos x}=\tan x \ \ ?$
  1. True

  2. False


Correct Option: A
Explanation:
LHS

$\dfrac{\sin 2x}{2\cos x}$

$\dfrac{2\sin x \cos x}{2\cos x}$

$\implies \dfrac{\sin x}{\cos x}$

$\implies \tan x $

Hence proved.

Which of the following is a non-positive and non-negative integer ?

  1. 1

  2. 0

  3. -1

  4. 3


Correct Option: B
Explanation:

The correct answer is 0 (b)

Since zero is neither positive nor negative .

Ram scored $30$% marks and failed by $15$ marks. Aditya score $40$% marks and obtained $35$ marks more than those required to pass. The pass percentage is?

  1. $33$%

  2. $38$%

  3. $43$%

  4. $46$%


Correct Option: A
Explanation:
Let the total no of marks for $x$
Let the passing marks for y
$\dfrac{30}{100}x+15=y$ ______(1)
$\dfrac{40}{100}x=y+35$
$\dfrac{40}{100}x-35=y$_______(2)
(1) - (2)
$\dfrac{-10x}{100}+50=0$
$\dfrac{10x}{100}=50\Rightarrow x=500$
$y=\dfrac{40}{100}\times 500-35=200-35=165$
$m\%$ of $x=y$
$\dfrac{m}{100}\times 500=165$
$m=33\%$

If $35\% $ of a number is $175$, then what percent of $175$ is that number ?

  1. $35\% $

  2. $65\% $

  3. $285.71\% $

  4. $420\% $


Correct Option: C
Explanation:
Let the required number be $x$

It is given that $35$% of that number is $175$

=> $\dfrac { 35 \times  x }{ 100 } =175$

=> $x= \dfrac { 175 \times  100 }{ 35 }$

=> $x= 500$

Now, the question requires the percentage that $500$ is of that number

Let that percentage be $y \%$.

Now, $\dfrac { y \times  175 }{ 100 } =500$

=>$ y=\dfrac { 500 \times  100 }{ 175 } $

=>$ y = 285.714$

Hence the answer is $ 285.71\%$

$2.7$ is what percent of $18$ ?

  1. $12$%

  2. $13$%

  3. $14$%

  4. $15$%


Correct Option: D
Explanation:

Percentage = $\dfrac {2.7}{18}$ $\times 100$


= $\dfrac {270}{18}$

= $\dfrac {30}{2}$ (removing common factor of 9)


= $15$%

If $2\, \displaystyle \frac{1}{2}\, \%$ofa a number is 0.2, then what will be 120 % of it?

  1. 10.8

  2. 4.8

  3. 9.6

  4. None


Correct Option: C
Explanation:

$2\, \displaystyle \frac{1}{2}\, \%$ of x = 0.2


$\displaystyle \frac{5}{200}\, \times\, x\, =\, 0.2$

$x\, =\, 0.2\, \times\, \displaystyle \frac{200}{5}\, =\, 8$

120 % of $8\, =\, \displaystyle \frac{120}{100}\, \times\, 8\, =\, 9.6$