Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

94751.

If [(2x - y,5),(3,y)] = [(6,5),(3,-2)], then x = (a) 3(b) 2(c) 5(d) 8

Answer»

Answer is (b) 2

94752.

What is ‘Longevity’?

Answer»

Life expectancy of new born baby is called ‘longevity’.

94753.

Define secular trend.

Answer»

A secular trend is a variable that evidences a consistent pattern within a given period of time. It is a statistical tendency that can be easily identified and it is not subject to seasonal or cyclical effects.

94754.

|(1,x,x2),(1,y,y2),(1,z,z2)| = 

Answer»

Answer is (d) (x - y)(y - z)(z - x)

94755.

Define type – I and type – II errors.

Answer»

Type I Error is taking a wrong decision to reject the null hypothesis when it is actually true. 

Type II Error is taking a wrong decision to accept the null hypothesis when it is actually not true.

94756.

Find the coordinates of the point where the line \(\frac{x+3}{3}\) = \(\frac{y-1}{-1}\) = \(\frac{z - 5}{-5}\) cuts the XY plane.

Answer»

The coordinates of the point are (0,0,0)

0,0,0 are the coordinates of intersection point
94757.

If z1 and z2 are two independent SNVs, then name the distribution of z12 , + z22 and find its mean.

Answer»

(z12, + z22,) ~ χ2(2) d.f. ie; is a chi-square distribution with n = 2 degress of freedom mean = n = 2.

94758.

tan-1 x = (a) cot-1 x(b) 1/cot-1 x(c) cot-1 1/x(d) - cot-1 x

Answer»

Answer is (c) cot-1 1/x

94759.

Write a merit of method least squares for measuring Trend.

Answer»

The method of least squares gives the most satisfactory measurement of the secular trend in a time series when the distribution of the deviations is approximately normal. The least-squares estimates are unbiased estimates of the parameters.

94760.

If Z1 and Z2 are two independent SNV’s, then name the distribution of Z12 + Z22 and find its mean.

Answer»

It is a chi-square distribution with 2 d.f. Mean = n = 2.

94761.

Write down the assumptions of interpolation and extrapolation.

Answer»

• The assumptions made in interpolation and extrapolations are: 

• There are no sudden jumps in the values of dependent variable(Y) from one period to another(X). 

• The rate of change of figures (Y) from one period to another(X) is uniform. 

• There will be no consecutive missing values in the series.

94762.

Write the Parameter of a Bernoulli distribution

Answer»

In the typical application of the Bernoulli distribution, a value of 1 indicates a "success" and a value of 0 indicates a "failure", where "success" refers that the event or outcome of interest. The parameter p in the Bernoulli distribution is given by the probability of a "success".

94763.

Write down the p.m.f. of Bernoulli distribution with parameter p = 0.4.

Answer»

p(x) = px q1 – x ; x = 0,1, : p(x) = 0.4x 0.61 – x ; x = 0,1

Here = 1 – p = 1 – 0.4 = 0.6

94764.

The principal value of sin-1 (√3/2) is(a) 2π/3(b) π/6(c) π/4(d) π/3

Answer»

Answer is (d) π/3

94765.

If f : N → N be defined by f(x) = 2x + 3 then f-1(x) =(a) 2x - 3(b) (x - 3)/2(c) (x + 3)/2(d) Not defined

Answer»

Answer is (b) (x - 3)/2

94766.

If f(x1) = f(x2) ⇒ x1 = x2, ∀ x1,x2 ∈ A, then what type of function is f : A → B ? (a) Onto (b) Many one (c) Constant (d) One-one 

Answer»

Answer is (d) One-one

94767.

If f(x1) = f(x2) ⇒ x1 = x2 ∀ x1, x2 ∈ A, then the function f : A → B is(a) one-one(b) constant(c) onto (d) many one

Answer»

Answer is (a) one-one

94768.

If f(x1) = f(x2) ⇒ x1 = x2 ∀ x1, x2 ∈ A, then what type of function is f : A → B?(a) One-One (b) Constant (c) Onto (d) Many one

Answer»

Answer is (a) One-One

94769.

State any two features of student /-distribution.

Answer»

n is the parameter, Mean = 0, Range = (-∞, ∞)

94770.

Define Point estimation and Interval estimation.

Answer»

‘While estimating the unknown parameter, if a specific value is proposed as an estimate, which is called Point estimation’. ‘While estimating the unknown parameter instead of a specific value, an interval is proposed, which is likely to contain the parameter is called Interval estimation’.

94771.

What is parameter space?

Answer»

Set of all admissible values of parameter is called parameter space.

94772.

For 10 samples of 5 items each, sum of sample means = 256.8 and ΣR = 7.85. Compute 3 sigma control limits for mean chart (for n = 5, A2 = 0.58).

Answer»

Given k = 10 ΣX̄ = 256.8 , Σ R = 7.85 , n = 5

Here standards are not given, 5 im

control limits for X̄ = charts are ,

C.L = X̄ = 25.68

L.C.L = X̄ – A2R̄= 25.68 

= 0.58 x 0.785 = 25.22

U.C.L = X̄ + A2R̄ 

= 25.68 – 0.58 x 0.785 

= 26.14

94773.

d/dx[sin-1x+cos-1x]=?(a) 0 (b) 1/√1-x2 (c) -1/√1-x2 (d) 1/2√1-x2

Answer»

correct option: (a) 0

94774.

In Statistical Hypothesis, if H1 : μ < 50 kg then write H0.

Answer»

H0: μ = 50,.

94775.

What are point estimation and interval estimation?

Answer»

Estimation of unknown parameter by proposing a specific value as an estimate is called point estimation. While estimating the unknown parameter by proposing an interval, which is likely to contain the parameter is called interval estimation.

94776.

What is meant by Statistical Quality Control?

Answer»

It is the method of controlling the quality of the products using statistical technique.

94777.

Write down two utilities of standard error.

Answer»

1. It is used in interval estimation, to write down the confidence intervals. 

2. It is used in testing of hypothesis to test whether the difference between the sample statistic and the population parameter is significant or not.

94778.

Find the initial basic feasible solution to the following transportation problem by NWCR method and find transportation cost to this solution.

Answer»

By N.W.C.R first allocation is made in the cell (1,1) as: Xu 

= Min(a, b) = m, n (500,400) 

= 40, and replace 500 by (500-400)= 100
Next allocation is made at (1,2)

94779.

What do you mean by process control and product control in statistical quality control?

Answer»

Controlling the quality of the product during the manufacturing process itself is the Process control. Controlling the quality of the finished products/ manufactured products is called product control.

94780.

∫dx/x2+16=?(a) 1/16 tan-1 x/16+k (b) 1/4tan-1 x/4+k (c) 1/4tan-1 4/x+k (d) 1/4tan-1 16/x2+k

Answer»

(b) 1/4tan-1 x/4+k

94781.

Which of the following is the unit matrix of order 3 x 3?

Answer»

Correct option (B)

94782.

Mention two method of obtaining initial basic feasible solution for a transportation problem.

Answer»

1. Matrix-Minim method and 

2. North-west corner rule.

94783.

In the set of all straight lines in a plane, the relation R "to be perpendicular" is -(a) Reflexive and transitive (b) symmetric and transitive (c) Symmetric (d) None of these

Answer»

Option: (c) Symmetric 

94784.

sin-1(1/√2)=?(a) π/4 (b) -π/4 (c) π/2 (d) -π/2

Answer»

correct option: (a) π/4

94785.

Integrating factor (I.F) of the differential equation dy/dx-y cosx = sin x cos x is -(a) e-sinx (b) esinx (c) e-cosx (d) ecosx

Answer»

option: (b) esinx

94786.

The sum of 5 consecutive even number is 80 what is the least even number.

Answer»

Let least even number is 2n - 4.

Therefore 5 consecutive even numbers are 2n - 4, 2n - 2, 2n, 2n + 2 and 2n + 4.

\(\therefore\) Their sum = (2n - 4) + (2n - 2) + 2n + (2n + 2) + (2n + 4)

 = 10 n

\(\therefore\) 10n = 80 (\(\because\) Given that sum of 5 consecutive even numbers is 80)

⇒ n = 80/10 = 8

\(\therefore\) least even number = 2n - 4 = 2 x 8 - 4 = 16 - 4 = 12

94787.

Find the square root of -7+21i

Answer»

Let \(\sqrt{-7+21i}\) = x + iy

⇒ (x + iy)2 = –7 + 21i  (By squaring both sides)

⇒ x2 + i2y2 + 2ixy = –7 + 21i (\(\because\) (a + b)2 = a2 + b2 + 2ab)

⇒ x2 – y2 + 2xyi = –7 + 21i  (\(\because\) i2 = –1)

⇒ x2 – y2 = –7 .........(1)

And 2xy = 21 ..........(2)     

(By comparing real and imaginary part of complex numbers)

\(\because\) (x2 + y2)2 = (x2 – y2)2 + 4x2y2    (\(\because\) (a + b)2 = (a – b)2 + 4ab)

= (–7)2 + (21)2   (From equation (1) and (2))

= 49 + 441

= 490

⇒ x2 + y2\(\sqrt{490}\) \(=7\sqrt{10}\) .......(3)

By adding equations (1) and (3), we get

2x2 = –7 + \(7\sqrt{10}\) 

⇒ x2\(\frac{7}{2}\)(–1 + \(\sqrt{10}\))

⇒ x \(=\pm\sqrt{\frac{7}{2}(-1+\sqrt{10})}\)  (\(\because \) \(\sqrt{10}\) > 1 ⇒ x is a real number)

By putting the value of x2 in equation (3), we get

y2\(7\sqrt{10}-\mathrm x^2\)

\(=7\sqrt{10}-\frac{7}{2}(-1+\sqrt{10})\)

\(=\frac{14\sqrt{10}+7-7\sqrt{10}}{2}\)

\(=\frac{7(\sqrt{10}+1)}{2}\)

⇒ y \(=\pm\sqrt{\frac{7}{2}(\sqrt{10}+1)}\)

\(\because \) xy = \(\frac{21}{2}> 0\)   (From equation (2))

\(\therefore\) x & y have same sign.

\(\therefore\) If x \(=\sqrt{\frac{7}{2}(-1+\sqrt{10})}\) then y \(=\sqrt{\frac{7}{2}(\sqrt{10}+1)}\)

Or

If x \(=-\sqrt{\frac{7}{2}(-1+\sqrt{10})}\) then y \(=-\sqrt{\frac{7}{2}(1+\sqrt{10})}\)

Hence, \(\sqrt{-7+21i}\) \(=\sqrt{\frac{7}{2}(\sqrt{10}-1}\) \(+i\sqrt{\frac{7}{2}(\sqrt{10}+1)}\)

\(=\sqrt{\frac{7}{2}}(\sqrt{\sqrt{10}-1}+i\sqrt{\sqrt{10}+1})\)

or  \(\sqrt{-7+21i}\) \(=-\sqrt{\frac{7}{2}(\sqrt{10}-1)}-i\sqrt{\frac{7}{2}\sqrt{10}+1}\)

\(=-\sqrt{\frac{7}{2}(\sqrt{10}-1)}+i\sqrt{\sqrt{10}+1}\)

Hence, the square root of –7 + 21i is \(\sqrt{\frac{7}{2}}\left(\sqrt{\sqrt{10}-1}+i\sqrt{\sqrt{10}+1}\right)\) or \(-\sqrt{\frac{7}{2}}\left(\sqrt{\sqrt{10}-1}+i\sqrt{\sqrt{10}+1}\right)\).

94788.

Angles of a quadrilateral are (4x), 5(x+2), (7x-20) and 6(x+3). Find the value of x and each angle of the quadrilateral

Answer»

Angles of quadrilateral are,

(4x)°, 5(x+2)°, (7x – 20)° and 6(x+3)°

∴ 4x + 5(x + 2) + (7x - 20) + 6(x + 3) = 360°

4x + 5x + 10 + 7x - 20 + 6x + 18 = 360°

22x + 8 = 360°

22x = 360° - 8°

22x = 352°

x = 16°

Hence angles are,

(4x)° = (4 × 16)° = 64°

5(x + 2)° = 5(16 + 2)° = 90°

(7x - 20)° = (7 × 16 - 20)° = 92°

6(x + 3)° = 6(16 + 3) = 114°

94789.

x(x-1)+x is a polynomail?

Answer»

Yes, it is a polynomial.
x(x-1)+x=x2-x+x=x2
As the above expression has a positive integer exponent for x, we can say that it is a polynomial.

94790.

In tossing a coin, find the probability of getting a tail?

Answer»

Favourable outcome (Getting a tail) =1
Total number of outcomes [H,T]=2
Probability = 1/2

94791.

Find the coefficient of x^2 in (x+2/x^2)^8

Answer» Find the coefficient of x^2 in (x+2/x^2)^8
94792.

The set N of natural numbers is:1. unbounded below in R2. bounded above in R3. unbounded above in R4. bounded above and bounded below in R

Answer» Correct Answer - Option 3 : unbounded above in R

Concept:

A natural number is a number that occurs commonly and obviously in nature. As such, it is a non-negative number. The set of natural numbers can be denoted by

N = {1, 2, 3, 4,....}

The set of natural numbers is bounded below and not bounded above in R.

We can prove not bounded above in R using contradiction.

Proof:

Assume by way of contradiction that N is a bounded above. Then, since N is not empty, it follows from the completeness axiom that sup(N) exists. Thus there must be m ∈ N such that

sup(N) - 1 < m (sup(N) means supremum of N or least upper bound)

⇒ sup(N) < m + 1

As m ∈ N , also m + 1 ∈ N, Which is a contradiction.

∴ N is not bounded above

94793.

If x, y, z are three consecutive positive integers, then log (1 + xz) is1. log y2. \(\log \dfrac{y}{2}\)3. log (2y)4. 2 log (y)

Answer» Correct Answer - Option 4 : 2 log (y)

Concept:

Logarithm Rule

log m= n log m

 

Calculations:

Let x, y, z are three consecutive positive integers.

⇒ y = x + 1 and z = y + 1

⇒ z = x + 2

Consider, log (1 + xz)

= log [1 + x(x+2)]

= log [1 + x2 + 2x]

= log (1 + x)2

= 2 log (1 + x)

= 2 log y

Hence, If x, y, z are three consecutive positive integers, then log (1 + xz) is 2 log y

94794.

If f(x)= x^(2) - x ^(2) where * denotes the greatest integer function and x in 0 n n in N then the number of elements in the

Answer»

f(x) is continuous only at one integral value of x which is x=1

f(x)=[x2]−[x]2
 
at x →1f(x)=0
at x →1+f(x) =1−1=0
so continuous at 1

94795.

If the relation R in the set {1,2,3} given by R={(1,2), (2,1), (1,1)}, then state if R is transitive relation, justify your answer

Answer»

We know that, for a relation to be transitive,

(x,y) ∈ R and (y, z) ∈ R then (x,z) ∈ R.

Here, (1,2) ∈ R and (2,1) ∈ R but (1,1) ∈ R.

R is transitive.

94796.

Evaluate \( \int_{0}^{2} \frac{5 x+4}{x^2+4} \)

Answer»

\(\int_0^2 \frac{5x+4}{x^2+4}dx\)

\(\frac{5}{2}\)\(\int_0^2 \frac{2x}{x^2+4}dx\) + 4 \(\int_0^2 \frac{1}{x^2+4}dx\) 

\(\frac{5}{2}\)\([log(x^2+4)]_0^2\) + \(\frac{4}{2}[tan^{-1}\frac{x}{2}]_0^2\) 

\(\frac{5}{2}\)(log 8 - log 4) + 2 (tan-11 - tan-10)

\(\frac{5}{2}\)log \(\frac{8}{4}\) + 2(\(\frac{\pi}{4}-0\))

\(\frac{5}{2}\) log 2 + \(\frac{\pi}{2}\)

94797.

Which of the following represents the thermite reaction ?A. `Fe_(2)O_(3) + CO rarr Fe+CO_(2)`B. `CaCO_(3) Cu (OH)_(2) rarr CaO + CO_(3) + H_(2)O`C. `Cu_(2)S + Cu_(2)O rarr Cu + SO_(2)`D. `Ma_(2)O_(3) + AJ rarr Mn + Al_(2)O_(3)`

Answer» Correct Answer - d
In the thermile reaction (aluminumathermic process alominium acts as a redacing agent , second one respresents a calclnation reaction while third one represents the self reduction process .
94798.

In Ellingham diagram, the slope of the curve of the formation metal oxide:A. is mostly `+ve`B. is mostly `-ve`C. depends on the type of metalD. depends on the formula of metal oxide

Answer» Correct Answer - A
By `Delta S =- ve`
`:.T Delta S` become more negative on increasing the temperature. `(Delta G = Delta H - T Delta S)`
94799.

Which of the following represents the thermite reaction ?A. `3Mn_(3)O_(4)+8A1 rarr9Mn+4A1_(2)O_(3)`B. `MgCO_(3)+SiO_(2)rarrMgSiO_(3) +CO_(2)`C. `Cu_(2)S+2Cu_(2)Orarr6Cu+S)_(2)`D. `Fe_(2)O_(3) +3COrarr 2Fe+3CO_(2)`

Answer» Correct Answer - A
94800.

An element having 17 protons and 18 neutron calculate number of electrons atomic number and Mass number.

Answer»

Mass number= 17+ 18 =35. Q. The atom of an element X contains 17 protons, 17 electrons and 18 neutrons whereas the atom of an element Y contains 11 protons, 11 electrons and 12 neutrons.

Given

no of electrons = 17

No of nuetrons = 18


no of protons = no of electrons


So no of protons = 17


Atomic number = no of electrons = no of protons


So atomic number = 17


Mass number = atomic no + no of nuetrons


So

Mass numb

er= 17+ 18 =35

Element of nucleus :

Protons:17

Neutron:18

So,  

=>Mass No. =17+18 = 35

And ,

=>No.  of electrons =17.  (as no. of electrons =no. of protons) 

And, 

=>Atomic No.  = 17

=>Name of element = Cl(chlorine)  


Hope it helps u.... ✌