Questions · Page 2 of 3

Write true or false if statement is wrong write the true statement.

Question 521 Mark
If $y=x^2$, then the rate of change of demand ( $x$ ) of a commodity with respect to its price $(y)$ is $\frac{1}{2 x}$
Answer
True
View full question & answer
Question 531 Mark
Optimal assignments are made in the Hungarian method to cells in the reduced matrix that contain a zero
Answer
True
View full question & answer
Question 541 Mark
For Cost of Living Index Number CLI $=\frac{\sum I W}{\sum W}$, where $I=\frac{P_0}{P_1} \times 100$ and $w=p_0 q_0$
Answer
False
View full question & answer
Question 551 Mark
Cyclical variation can occur several times in a year.
Answer
This statement is False.

Explanation:

Seasonal variation can occur several times in a year.

View full question & answer
Question 571 Mark
State whether the following statement is True or False:
A factor is an agent who is given the possession of goods and enters a contract for sale in his/her own name
Answer
True
View full question & answer
Question 581 Mark
State whether the following statement is True or False:
Order and degree of differential equation are always positive integers.
Answer
True
View full question & answer
Question 601 Mark
If $\int x e ^{2 x} dx$ is equal to $e ^{2 x} f ( x )+ c$, where $c$ is constant of integration, then $f ( x )$ is $\frac{2 x-1}{2}$.
Answer
False

Explanation:
$ \text { Let } I =\int x \cdot e ^{2 x } dx$
$= x \int e ^{2 x } \cdot dx -\int\left[\frac{ d }{ dx }( x ) \int e ^{2 x } \cdot dx \right] dx$
$= x \cdot \frac{ e ^{2 x }}{2}-\int 1 \cdot \frac{ e ^{2 x }}{2} \cdot dx$
$=\frac{ x }{2} e ^{2 x }-\frac{1}{2} \int e ^{2 x }+ c$
$=\frac{ x }{2} e ^{2 x }-\frac{1}{2} \cdot \frac{ e ^{2 x }}{2}+ c$
$= e ^{2 x }\left(\frac{ x }{2}-\frac{1}{4}\right)+ c$
$= e ^{2 x }\left(\frac{2 x -1}{4}\right)+ c $
$\therefore f(x)=\frac{2 x-1}{4}$
View full question & answer
Question 631 Mark
To convert the assignment problem into maximization problem, the smallest element in the matrix is to deducted from all other elements
Answer
False
View full question & answer
Question 641 Mark
The three types of Index numbers are
i. Price Index Number
ii. Quantity Index Number
iii. Value Index Number
Answer
True
View full question & answer
Question 651 Mark
State whether the following statement is True or False:
Seasonal variation can be observed over several years
Answer
True
View full question & answer
Question 671 Mark
State whether the following statement is True or False:
The trade discount is first calculated on the catalogue (list) price
Answer
True
View full question & answer
Question 681 Mark
State whether the following statement is True or False:
The integrating factor of the differential equation $\frac{ d y}{ d x}-y= x$ is $e ^{- x }$
Answer
True
View full question & answer
Question 701 Mark
The proper substitution for $\int x\left(x^x\right)^x(2 \log x+1) d x$ is $\left(x^x\right)^x= t$
Answer
True
Explanation:
Let $I=\int x\left(x^x\right)^x(2 \log x+1) d x$
Put $\left( x ^{ x }\right)^{ x }= t$

Taking logarithm of both sides, we get
$ \log \left( x ^{ x }\right)^{ x }=\log t$
$\therefore x ^2 \cdot \log x =\log t $
Differentiating w.r.t. $x$, we get
$ x ^2 \cdot \frac{1}{ x }+(\log x ) \cdot 2 x =\frac{1}{ t } \cdot \frac{ dt }{ dx }$
$\therefore( x +2 x \log x ) dx =\frac{1}{ t } \cdot dt$
$\therefore x (1+2 \log x ) dx =\frac{1}{ t } \cdot dt $
$\therefore I =\int t \cdot \frac{1}{ t } \cdot dt =\int 1 \cdot dt = t + c =\left( x ^{ x }\right)^{ x }+ c$
View full question & answer
Question 731 Mark
The objective of an assignment problem is to assign number of jobs to equal number of persons at maximum cost
Answer
False
View full question & answer
Question 741 Mark
Walsh's Price Index Number is given by $\frac{\sum p_1 \sqrt{q_0 q_1}}{\sum p_0 \sqrt{q_0 q_1}} \times 100$
Answer
True
View full question & answer
Question 751 Mark
State whether the following statement is True or False:
The secular trend component of time series represents irregular variations
Answer
False
View full question & answer
Question 781 Mark
In sequencing problem each job once started on any machine must be processed still its completion
Answer
True
View full question & answer
Question 791 Mark
The function $y = cx$ is the solution of differential equation $\frac{ d y}{ d x}=\frac{y}{x}$
Answer
This statement is True.
View full question & answer
Question 821 Mark
In sequencing problem the processing times are dependent of order of processing the jobs on machine
Answer
False
View full question & answer
Question 841 Mark
After applying elementary transformation $R_1-3 R_2$ on matrix $\left[\begin{array}{cc}3 & -2 \\ 1 & 4\end{array}\right]$ we get $\left[\begin{array}{cc}0 & -12 \\ 1 & 4\end{array}\right]$
Answer
False
View full question & answer
Question 851 Mark
State whether the following statement is True or False:
If equation of regression lines are $3 x+2 y-26=0$ and $6 x+y-31=0$, then mean of $X$ is 7
Answer
False
View full question & answer
Question 881 Mark
State whether the following statement is True or False:
If $u=x-a$ and $v=y-b$ then $b_{x y}=b_{u v}$
Answer
True
View full question & answer
Question 891 Mark
State whether the following statement is True or False:
An annuity where payments continue forever is called perpetuity
Answer
True
View full question & answer
Question 911 Mark
$\left[\begin{array}{ccc}2 & 0 & 0 \\ 3 & -1 & 0 \\ -7 & 3 & 1\end{array}\right]$ is a skew symmetric matrix
Answer
False
View full question & answer
Question 921 Mark
State whether the following statement is True or False:
The following data is not consistent: $b_{y x}+b_{x y}=1.3$ and $r=0.75$
Answer
True
View full question & answer
Question 931 Mark
State whether the following statement is True or False:
Annuity contingent begins and ends on certain fixed dates
Answer
False
View full question & answer
Question 951 Mark
Matrix $\left[\begin{array}{ccc} a & b & c \\ p & q & r \\ 2 a - p & 2 b - q & 2 c - r \end{array}\right]$ is a singular
Answer
True.
View full question & answer
Question 961 Mark
State whether the following statement is True or False:
If $b_{x y}<0$ and $b_{y x}<0$ then ' $r$ ' is $>0$
Answer
False
View full question & answer
Question 971 Mark
State whether the following statement is True or False:
The future value of an annuity is the accumulated values of all instalments
Answer
True
View full question & answer
Question 991 Mark
If $A=\left[\begin{array}{ccc}1 & 2 & -5 \\ 2 & -3 & 4 \\ -5 & 4 & 9\end{array}\right]$, then $A^{\top}=A$
Answer
True
View full question & answer
Question 1001 Mark
State whether the following statement is True or False:
Correlation analysis is the theory of games
Answer
False
View full question & answer
Write true or false if statement is wrong write the true sta - Page 2 - Maths (commerce) STD 12 Commerce / Arts Questions - Vidyadip