12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications மின்னணு தரவு பரிமாற்றம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிக பாதுகாப்பு அமைப்புகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின்னணு செலுத்தல் முறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications திறந்த மூல கருத்துருக்கள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு வடமிடல் Sample Question Papers Study Material - QB365 Set A

Published on: 23/06/2021
QB365 provides detailed and simple solution for every
Creative Questions in class 12 Business Maths Subject.It will helps to get more idea about question pattern in
every Creative questions with solution.
Download Tamil Nadu 12th Standard Business Maths and Statistics question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Business Maths and Statistics Test

1.
Obtain K, μ and σ2 of of the normal distribution whose probability distribution function is f(x) = \(K{ e }^{ -2x^{ 2 }+4x-2 }\), -∞
2.
Find the value of K if X is a normal variate whose p.d.f is given by f(x) = \(\frac { 1 }{ K } \)e8x-4x2, -∞
3.
If a random variable X follows Poisson distribution such that P(X = 2) = 9. P(X = 4) + 90 P(X = 6) then find the mean and variance.
4.
The standard deviation of a binomial distribution (q +p)16 is 2. Find its mean.
5.
The probability that an event A happens in one treat of an experiment is 0.4. Three independent treats of the experiment are performed. Find the p!probability that the event A happens at least once.
1.
Consider -2x2 + 4x - 2 = -2(x2-2x+1)
= -2(x-1)2
∴ \({ e }^{ -2x^{ 2 }+4x-2 }=e^{ -2(x-1)^{ 2 } }\)
\({ e }^{ -\frac { 1 }{ 2 } \frac { (x-1)^{ 2 } }{ \frac { 1 }{ 4 } } }=e^{ -\frac { 1 }{ 2 } \left( \frac { x-1 }{ \frac { 1 }{ 2 } } \right) ^{ 2 } }\)
i.e \(K{ e }^{ -2x^{ 2 }+4x-2 }=\frac { 1 }{ \sigma \sqrt { 2\pi } } .e^{ -\frac { 1 }{ 2 } \left( \frac { x-\mu }{ \sigma } \right) }\)
⇒ \(Ke^{ -\frac { 1 }{ 2 } \left( \frac { x-1 }{ \frac { 1 }{ 2 } } \right) ^{ 2 } }=\frac { 1 }{ \sigma \sqrt { 2\pi } } .e^{ -\frac { 1 }{ 2 } \left( \frac { x-\mu }{ \sigma } \right) }\)
⇒ σ = \(\frac{1}{2}\), μ = 1 and K = \(\frac { 1 }{ \sigma \sqrt { 2\pi } } \)
⇒ K = \(\frac { 1 }{ \frac { 1 }{ 2 } .\sqrt { 2\pi } } \Rightarrow K=\sqrt { \frac { 2 }{ \pi } } \).
2.
The p.d.f for the normal distribution is
f(x) = \(\frac { 1 }{ \sigma \sqrt { 2\pi } } .e^{ -\frac { 1 }{ 2 } \left( \frac { x-\mu }{ \sigma } \right) ^{ 2 } }\), -∞
f(x) = \(\frac { 1 }{ K } { e }^{ 8x-4x^{ 2 } }\)
= \(\frac { 1 }{ K } e^{ -4 }({ x }^{ 2 }-2x)\)
= \(\frac { 1 }{ K } e^{ -4 }({ x }^{ 2 }-2x+1-1)\)
\(\frac { 1 }{ K } e^{ -4 }(x-1)^{ 2 }+4\)
=\(\frac { 1 }{ K } .{ e }^{ 4 }e^{ -\frac { 1 }{ 2 } \frac { x-1^{ 2 } }{ \frac { 1 }{ 8 } } }\)
=\(\frac { 1 }{ 4 } { e }^{ 4 }e^{ -\frac { 1 }{ 2 } \left( \frac { x-1 }{ \frac { 1 }{ \sqrt { 8 } } } \right) ^{ 2 } }\) ...(2)
From (1) & (2), μ = 1, σ = \(\frac { 1 }{ \sqrt { 8 } } \) and
\(\frac { 1 }{ \sigma \sqrt { 2\pi } } =\frac { 1 }{ K } e^{ 4 }\)
\(\frac { 1 }{ \frac { 1 }{ \sqrt { 8 } } .\sqrt { 2 } \pi } =\frac { 1 }{ K } e^{ 4 }\)
⇒ \(\frac { \sqrt { 8 } }{ \sqrt { 2\pi } } =\frac { 1 }{ K } e^{ 4 }\)
\(\sqrt { \frac { 4 }{ \pi } } =\frac { 1 }{ K } { e }^{ 4 }\)
∴ K = \({ e }^{ 4 }\times \sqrt { \frac { \pi }{ 4 } } \)
3.
Given P(X = 2) = 9 P(X = 4) + 90 P(X = 6)
Since X follows Poisson distribution with
P(X,λ) = \(\frac { { e }^{ -\lambda }.{ \lambda }^{ 0 } }{ x! } \)
\(\frac { { e }^{ -\lambda }.{ \lambda }^{ 2 } }{ 2! } =\frac { { e }^{ -\lambda }.{ \lambda }^{ 4 } }{ 4! } +\frac { { 90e }^{ -\lambda }.{ \lambda }^{ 6 } }{ 6! } \)
⇒ \(\frac { 1 }{ 2 } =\frac { 3{ \lambda }^{ 2 }+\lambda ^{ 4 } }{ 8 } \)
⇒ λ4+3λ2 = 4
⇒ λ4+ 3λ2-4 = 0
Put λ2 = t
⇒ t2 + 3t-4 = 0 ⇒ (t-1)(t + 4) = 0
⇒ t = 1 or t = -4
∴ t = 1 [t = -4 is not possible]
∴ λ2 = 1 ⇒ λ = 1
∴ Mean = 1
For Poisson distribution, mean = variance = 1
4.
Given n = 16, S.D = 2 ⇒ \(\sqrt { npq } \) =2
⇒ npq = 4
∴ 16(pq) = 4 ⇒ pq =\(\frac { 4 }{ 16 } =\frac { 1 }{ 4 } \)
⇒ q = \(\frac { 1 }{ 4p } \)...(1)
Since p + q = 1 ⇒ p+\(\frac { 1 }{ 4p } \)=1
⇒ \(\frac { 4{ p }^{ 2 }+1 }{ 4p } \) = 1
⇒ 4p2+1 = 4p ⇒ 4p2 -4p+1 = 0
⇒ (2p-1)2 = 0 ⇒ 2p-1 = 0
⇒ 2p = 1 ⇒ p = \(\frac { 1 }{ 2 } \)
∴ q = 1-p = \(1-\frac { 1 }{ 2 } =\frac { 1 }{ 2 } \)
Mean = np = 16 x \(\frac { 1 }{ 2 } \) = 8
5.
p = 0.4, n = 3
q =1 - P = 1 - 0.4 = 0.6
P(X = x) = nCx pxqn-x
P(X≥1) = P(X = 1) + P(X = 2) + P(X = 3)
=3C1 (0.4)1 (0.6)2 + 3C2 (0.4)2 (0.6) + 3C3 (0.4)3 (0.6)0
=3 x \(\left( \frac { 4 }{ 10 } \right) \left( \frac { 36 }{ 100 } \right) +3\left( \frac { 16 }{ 100 } \right) \left( \frac { 6 }{ 100 } \right) +\left( \frac { 64 }{ 1000 } \right) \)
= \(\frac { 1 }{ 1000 } \)(432+288+64) =\(\frac { 784 }{ 1000 } \)
P(X≥1) = 0.784
12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications களப்பெயர் முறைமை (DNS) Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு எடுத்துக்காட்டுகள் மற்றும் நெறிமுறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications கணினி வலையமைப்பு ஓர் அறிமுகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications PHP-உடன் MySQL-ஐ இணைத்தல் Sample Question Papers Study Material - QB365 Set A
Tamilnadu Stateboard 12th Standard Subjects

Maths

Chemistry

Physics

Biology

Computer Science

Business Maths and Statistics

Economics

Commerce

Accountancy

History

Computer Applications

Biology

Computer Technology

Computer Applications

Computer Science

Business Maths and Statistics

Commerce

Economics

Maths

Chemistry

Physics

Computer Technology

History

Accountancy

Tamil

English

French
Tamilnadu Stateboard Standards