Tag: maths

Questions Related to maths

The conditional $( p \wedge q ) \Rightarrow p$ is 

  1. neither tautology nor contradiction

  2. a tautology

  3. a contradiction

  4. both tautology and contradiction


Correct Option: B

Boolean algebra is also called

  1. switching algebra

  2. arithmetic algebra

  3. linear algebra

  4. algebra


Correct Option: A
Explanation:

Boolean algebra is also called switching algebra..


It was invented by mathematician George Boole in 1849.Boolean algebra or 

switching algebra ia a system of mathematical logic to perform different 

mathematical operation in binary system.

$e*x=x*e=x$ is the

  1. commutative property

  2. inverse property

  3. associative property

  4. identity element


Correct Option: D
Explanation:

Given, $e\times x=x\times e=x$

This is possible when $e=1$
This is an identity element.

A Boolean function may be transformed into

  1. logical diagram

  2. logical graph

  3. map

  4. matrix


Correct Option: A
Explanation:

Boolean function:

        It can be represented in the form of diagram with logic gates.

Boolean algebra theorem, gives   $x\cdot (x+y)$   equal to

  1. $x'$

  2. $1$

  3. $x$

  4. $0$


Correct Option: C
Explanation:

    $x\cdot \left( x+y \right) $

$=x\cdot x+xy$
$=x$

To perform product of maxterms Boolean function must be brought into

  1. and terms

  2. or terms

  3. not terms

  4. nand terms


Correct Option: B
Explanation:

For performing Product of Maxterms, it has to be brought into POS, i.e; Product of Sum form. For this, the Boolean Function must be brought into OR terms.

Minterms are also called

  1. standard sum

  2. standard product

  3. standard division

  4. standard subtraction


Correct Option: B
Explanation:

product is called a minterm because it has minimum-satisfiability where as a sum is called a maxterm because it has maximum-satisfiability among all practically interesting boolean functions.

The ratio of the present age of Manoj to that of Wasim is $3:11$. Wasim is $12\ yr$ younger than Rehana. Rehanas age after $7\ yr$ will be $85\ yr$. What is thepresent age of Manojs father, who is $25\ yr$ older than Manoj?

  1. $43\ yr$

  2. $67\ yr$

  3. $45\ yr$

  4. $69\ yr$


Correct Option: A
Explanation:

 the present age of Wasim $=11x$

 present age of Manoj $=3x$

 present age of Rehana $=11x+12$
 present age of Manoj's father $=3x+25$

 after $7$ years, Rehana's age is $85$ years. 
 $11x+12+7=85$
 $ 11x=66$
 $x=6$
 
age of Manoj's father $=3 \times  6 + 25 = 43$ years. 

The sum of three consecutive odd numbers is $38$ more than the average of these numbers. What is the first number

  1. $13$

  2. $17$

  3. $19$

  4. Data inadequate

  5. None of these


Correct Option: B
Explanation:
let $'a'$ be the first odd number

As per Question

$ a+a+2+a+4 = 38 +\dfrac{a+a+2+a+4}{3}$

$ \Rightarrow 3a+6 = 38+a+2 $

$ \Rightarrow 2a = 34$

$ \Rightarrow a = 17 $

Solve $3x-450=2x-240$.

  1. $210$

  2. $230$

  3. $220$

  4. $200$


Correct Option: A
Explanation:

We have,

$3x-450=2x-240$

$3x-2x=450-240$

$x=210$

Hence, this is the answer.