# Math for Computer science Questions and Answers 181 to 190

## Math for Computer science

### Questions  181 to 190

181.
If a procedure is broken into a sequence of two tasks. If there are n1 ways to do the first task
and n2 ways to do the second task, then there are _____ ways to do the procedure.
 (a) n1-n2 (b) n1+n2 (c) n1x n2 (d) n1/n2 (e) n1 | n2.
182.
If first task can be done in n1 ways, second task can be done in n2 ways, and if
both cannot be done at the same time, then, the total number of ways to do the task is
 (a) n1-n2 (b) n1+n2 (c) n1*n2 (d) n1/n2 (e) n1 | n2.
183.
The Cryptosystem based on Modular Exponentiation Modulo and  the product of two
large prime numbers is called as
 (a) RSA Encryption (b) DES Encryption (c) CRC Encryption (d) PGP Encryption (e) Affine Transformation.
184.
The total number of r-combinations from a set with n-elements when repetition of
elements is allowed is
 (a) C(n + r –1) (b) C(n – r –1) (c) C(n + r + 1) (d) C(n – r + 1) (e) C( (n / r) + 1).
185.
In Hashing, when more than one file is assigned to single memory location, then it is called as
 (a) Collection (b) Crashing (c) Chaining (d) Collision (e) Coherence.
186.
The product of two numbers is
27.3852.7.11 and their gcd is 23.34.5. What is their LCM?
 (a) 24.33.5.711 (b) 24.3.5.7 (c) 24.34.5.711 (d) 2.34.5.711 (e) 2.3.5.7.
187.
What is the probability that a randomly selected day of a leap year is in February?
 (a) 28/365 (b) 28/366 (c) 29/365 (d) 29/366 (e) 30/366.
188.
What is the probability that a card chosen randomly from a deck is an ace or a heart?
 (a) 13/52 (b) 1/13 (c) 16/52 (d) 17/52 (e) 4/13.
189.
Which of the following condition is true with respect to the probability of a sample
space p(S) Where S is the sample space?
 (a) p(S)  > 1 (b) 0 < p(S) >1 (c) 1> p(S) ≥ 2 (d) p(S) = 0 (e) p(S) = 1.
190.
What is the probability that a number selected within the range of 1…100, is divisible by 5?
 (a) 1 / 20 (b) 1 / 5 (c) 1 / 25 (d) 1 / 4 (e) 1/ 100.