Question

1. Which number is neither a prime number nor a composite number?



2. Which of the following are pairs of co-primes?

(i) 8, 14

(ii) 4, 5

(iii) 17, 19

(iv) 27, 15



3. List the prime numbers from 25 to 100 and say how many they are.



4. Write all the twin prime numbers from 51 to 100.



5. Write 5 pairs of twin prime numbers from 1 to 50.



6. Which are the even prime numbers?
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Answer 1

Answer:

1)1

2)4,5

3)There are a total of 16 prime numbers between 25 and 100 which are 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97.

4)Twin primes between 51 and 100 are (59,61) and (71,73).

5)The first few twin prime pairs are: (3, 5), (5, 7), (11, 13), (17, 19), (29, 31), (41, 43), (59, 61), (71, 73), (101, 103), (107, 109), (137, 139),

6)Only 2 is even prime number

Answer 2

Answer:

1. one is neither prime nor composite number.

2.option(iii)17,19.

3.29,31,37,41,43,53,59,61,67,73,79,83,89,97. they 14.

4.59,61;71,73.

5.3,5;17,19;29,31;41,43;11,13

6.2is only number which is even prime number.