Chapter: Unit 1

1. |
## Let A={a, b, {c, d}, e}. How many elements does A contain? |

A. | 1 |

B. | 2 |

C. | 3 |

D. | 4 |

Answer» D. 4 |

2. |
## Let A={2,{4,5},4} Which statement is correct? |

A. | 5 is an element of A. |

B. | {5} is an element of A. |

C. | {4, 5} is an element of A. |

D. | {5} is a subset of A. |

Answer» C. {4, 5} is an element of A. |

3. |
## Which of these sets is finite? |

A. | {x | x is even} |

B. | ) {1, 2, 3,...} |

C. | {1, 2, 3,...,999,1000} |

D. | none |

Answer» C. {1, 2, 3,...,999,1000} |

4. |
## Which of these sets is not a null set? |

A. | A = {x | 6x = 24 and 3x = 1} |

B. | B = {x | x + 10 = 10} |

C. | C = {x | x is a man older than 200 years} |

D. | D = {x | x < x} |

Answer» B. B = {x | x + 10 = 10} |

5. |
## . Let S={1, 2, 3}. How many subsets does S contain? |

A. | 3 |

B. | 6 |

C. | 8 |

D. | 4 |

Answer» C. 8 |

6. |
## . Which set S does the power set 2S = {Ф,{1}, {2}, {3}, {1, 2}, {1, 3}, {2, 3}, {1, 2, 3}} come from? |

A. | {{1},{2},{3}} |

B. | {1, 2, 3} |

C. | {{1, 2}, {2, 3}, {1, 3}} |

D. | {{1, 2, 3}} |

Answer» B. {1, 2, 3} |

7. |
## Let A = {x, y, z}, B = {v, w, x}. Which of the following statements is correct? |

A. | A U B ={v, w, x, y, z} |

B. | A U B = {v, w, y, z} |

C. | A U B = {v, w, x, y} |

D. | A U B ={x, w, x, y, z} |

Answer» A. A U B ={v, w, x, y, z} |

8. |
## which sets are equal ? 1.{r,s,t} 2.{s,s,t,r} 3.{t,r,t,s} |

A. | 1 and 2 |

B. | 2 and 3 |

C. | 1 and 3 |

D. | all are equal |

Answer» D. all are equal |

9. |
## A U A=A according to …….law |

A. | Associative law |

B. | commutative law |

C. | Indempotent law |

D. | distributive law |

Answer» C. Indempotent law |

10. |
## In any application of the theory of sets, the members of all the sets belongs to …… set |

A. | union |

B. | intersection |

C. | universal |

D. | cardinal |

Answer» C. universal |

11. |
## let A={{a,b}} then aЄ A |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» B. FALSE |

12. |
## ФЄФ |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» B. FALSE |

13. |
## The sets {a,b,c} and {b,c,a} represnet the same sets. |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» A. TRUE |

14. |
## Cardinality of a set is number of element of the set. |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» A. TRUE |

15. |
## Multiset is an unordered collection of elemnts where an element can occur a a member more than once |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» A. TRUE |

16. |
## one of the A or B is uncountably infinite and one is countably infinite then | AUB| will be |

A. | countably infinite |

B. | uncountably finite |

C. | countably finite |

D. | uncountably infinite |

Answer» D. uncountably infinite |

17. |
## Sum of first n positive integers is |

A. | n(n+1) |

B. | n |

C. | n(n+1)0.5 |

D. | n(n+2) |

Answer» C. n(n+1)0.5 |

18. |
## Let P(S) denote the power set of set S. which of the is always true |

A. | P(P(s))=p(s) |

B. | P(S)∩ S= P(S) |

C. | P(S)∩P(P(S)) ={Ф} |

D. | None |

Answer» C. P(S)∩P(P(S)) ={Ф} |

19. |
## {3}Є{1,3,5} |

A. | TRUE |

B. | FALSE |

C. | Both |

D. | None |

Answer» B. FALSE |

20. |
## consider the following data for 120 mathematics students at a college concerning the languages French,Gernan, and russian: 65 study frensh, 45 study german 42 study russian , 20 study french and german, 25 study french and russian, 15 study german and russian. 8 study all three languages. Determine how many students study exactly 1 subject? |

A. | 100 |

B. | 25 |

C. | 56 |

D. | 20 |

Answer» C. 56 |

21. |
## ……… is an unordered collection of elements where an element can occur as a member more than once |

A. | Multiset |

B. | ordered set |

C. | set |

D. | None |

Answer» A. Multiset |

22. |
## In a room containing 28 females, there are 18 females who speak English, 15 females speak french and 22 speak german. 9 females speak both english and french, 11 females speak both french and german where as 13 speak both german and english. How many females speak all 3 languages? |

A. | 9 |

B. | 8 |

C. | 7 |

D. | 6 |

Answer» D. 6 |

23. |
## If U = {1, 2, 3, . . . 10 } and S = { 4, 5, 6, 7, 8 }, then S ' = |

A. | { 9, 10 } |

B. | {1, 2, 3 } |

C. | {1, 2, 3 9 } |

D. | {1, 2, 3 9 10 } |

Answer» D. {1, 2, 3 9 10 } |

24. |
## If U = {1, 2, 3, . . . 20 } and S = set of prime numbers , then S = |

A. | { 3, 5, 7, 11, 13, 17 } |

B. | { 2, 3, 5, 7, 11, 13, 17, 19 } |

C. | {1, 3, 5, 7, 9, 11, 13, 15, 17, 19 } |

D. | {1, 2, 3, 5, 7, 11, 13, 17 } |

Answer» B. { 2, 3, 5, 7, 11, 13, 17, 19 } |

25. |
## Consider the statement,“If n is divisible by 30 then n is divisible by 2 and by 3 and by 5.”Which of the following statements is equivalent to this statement? |

A. | If n is not divisible by 30 then n is divisible by 2 or divisible by 3 or divisible by 5 |

B. | If n is not divisible by 30 then n is not divisible by 2 or not divisible by 3 or not divisible by 5 |

C. | If n is divisible by 2 and divisible by 3 and divisible by 5 then n is divisible by 30. |

D. | If n is not divisible by 2 or not divisible by 3 or not divisible by 5 then n is not divisible by 30 |

Answer» D. If n is not divisible by 2 or not divisible by 3 or not divisible by 5 then n is not divisible by 30 |

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