# PSC Vocational Teacher in Computer Science Model Questions and Answers

PSC Vocational Teacher in Computer Science Model Questions and Answers: Here are the model questions and answers for Vocational Teacher in Computer Science PSC examination. These are the previous asked questions for the PSC Vocational Teacher in Computer Science Examination.

## PSC Vocational Teacher in Computer Science Model Questions and Answers

**1. gcd(272, 1479) is …………**

(A) 17 (B) 7

(C) 11 (D) 3

Answer: A

**2. The solution to the system of linear congruence.**

**7x+3y≡10(mod 16) and**

**2x+5y≡9(mod 16) is:**

(A) x≡2(mod 16) and y≡7(mod 16)

(B) x≡3(mod 16) and y≡7(mod 16)

(C) x≡3(mod 16) and y≡6(mod 16)

(D) x≡2(mod 16) and y≡6(mod 16)

Answer: B

**3. Which one of the following field is a finite field?**

(A) Z12 (B) Z13

(C) Z14 (D) Z15

Answer: B

**4. Which one of the following is not a Carmichael number?**

(A) 1105 (B) 2465

(C) 561 (D) None of the above

Answer: D

**5. If there are m people in a group who need to communicate with each other, how many keys are needed for symmetric key cryptography?**

(A) (m-1) (B) m

(C) m*(m-1) (D) (m*(m-1))/2

Answer: D

**6. Brute force attack is also known as ……………. attack.**

(A) pattern attack (B) cipher only

(C) statistical (D) exhaustive key search

Answer: D

**7. Combination traditional additive and multiplicative cipher is:**

(A) Affine (B) Ceaser

(C) Hill (D) None of these

Answer: A

**8. Find the result of 710 mod 11 using Fermat’s little theorem:**

(A) 2 (B) 1

(C) 3 (D) None of these

Answer: B

**9. For the one way function Y=f(x), X=f-1(Y) is:**

(A) Feasible (B) Infeasible

(C) Not predicted (D) None of these

Answer: B

**10. In an RSA algorithm if p=7, q=11, then Φ(n) equal to …………..**

(A) 61 (B) 77

(C) 76 (D) none of these

Answer: D

**11. In an L.P.P. a non-negative variable added to the constraint inequality to convert it into equality is known as ……………. variable.**

(A) slack (B) surplus

(C) artificial (D) none of these

Answer: A

**12. An L.P.P which feasible solution is having unbounded optimal solution, then its dual is having …………….. solution**

(A) an optimal (B) a feasible

(C) no feasible (D) none of these

Answer: C

**13. To balance an unbounded transportation problem, where total requirement is less than total availability, it is to introduce ……………**

(A) A dummy destination (B) A dummy source

(C) A dummy cell (D) None of these

Answer: A

**14. The method used for solving an assignment problem is:**

(A) Revised simplex (B) Hungarian

(C) Vogel’s approximation (D) none of these

Answer: B

**15. If the number of arrivals in a queue in time ‘t’ follows Poisson distribution, inter arrival time follows:**

(A) Poisson distribution (B) Normal distribution

(C) Exponential distribution (D) None

Answer: C

**16. In a Poisson queue with arrival rate λ and service rate μ, the probability that the queuelength exceeds n is:**

(A) (λ/μ)n (B) 1-(λ/μ)n

(C) (λ+μ)/λ (D) none of these

Answer: A

**17. A game with game matrix [aij] is said to be fair, if:**

(A) Maxi Minj aij>Minj Maxi aij

(B) Maxi Minj aij<Minj Maxi aij

(C) Maxi Minj aij=Minj Maxi aij

(D) none of these

Answer: C

**18. Obtain the mixed strategy for the game with payoff matrix**

(A) (1/4,3/4) (B) (3/4,1/4)

(C) (1/2,1/2) (D) none of these

Answer: A

**19. In an inventory control model, time between placing an order and its arrival in stock is:**

(A) Set up time (B) Lead time

(C) Order time (D) None of these

Answer: B

**20. Customer arrives in a single man service counter according to Poisson process. Average arrival rate is 20 per hour and average service rate is 36 per hour then the average waiting time of a customer in the queue is,**

(A) 110 sec (B) 125 sec

(C) 140 sec (D) none of these

Answer: B

**21. In algorithms O(n2) is called:**

(A) linear (B) exponential

(C) quadratic (D) none of these

Answer: C

**22. Control abstraction is a term related to:**

(A) dynamic programming (B) greedy

(C) backtrack (D) none of these

Answer: D

**23. Performance measure of an algorithm is concerned with obtaining the space and …………. requirement.**

(A) Complexity (B) Time

(C) Direction (D) None of these

Answer: B

**24. The name backtrack was first coined by:**

(A) D.H. Lehmer (B) R.J. Waker

(C) S. Golomb (D) L. Baumest

Answer: A

**25. In a state space tree a node which has been generated and all of whose children have not yet been generated is called:**

(A) dead node (B) leaf node

(C) live node (D) none of these

Answer: C