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Write two prime numbers whose sum is also a prime number.

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Important Questions on Playing with Numbers

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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Consider the pairs of prime numbers (m, n) between 50 and 100 such that m-n=6. How many such pairs are there?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Three numbers which are co-prime to each other, are such that the product of the first two is 286 and that of the last two is 770. What is the sum of the three numbers?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Find the mean of the first 6 prime numbers.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
The sum of the squares of the digits of the largest two-digit prime number is:
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers

The HCF of two co-prime numbers is :

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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
The number of prime numbers which are less than 100 is:
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
One fourth of the sum of the prime numbers, greater than 4 but less than 16, is the square of
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
a, b, c, d are non-zero integers such that (ab) divides (cd). If a and c are coprime, then which one of the following is correct?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Which of the following is not a pair of prime numbers ?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Which of the following number is an odd and prime number?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Write seven consecutive composite numbers less than 100 having no prime number between them.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers

Following pair of numbers are co-prime?

13 and 16

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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
What are twin primes? Write all the pairs of twin primes between 50 and 100.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
What are composite numbers? Can a composite number be odd? If yes, write the smallest odd composite number.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Sum of the number of primes between 16 to 80 and 90 to 100 is:
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
Write the smallest prime number.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers

Check whether the given number is prime or not.
 103

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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers

Answer in one Word or a Line

Are two co-prime numbers always prime? is the converse true?
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
What are prime numbers? Give ten examples.
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Mathematics>Arithmetic>Playing with Numbers>Prime and Composite Numbers
What are co-primes? Give examples of five pairs of co-primes. Are co-primes always primes? If no, illustrate your answer by an example.