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What are the prime numbers between 20 and 50?

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by seeing the prime number table we know that 25 prime numbers are existing in between 1 to 100
the following table explains


Prime numbers

1-25
2,3,5,7,11,13,17,19,23
9
26-50
29,31,37,41,43,47
6
51-75
53,59,71,73,61,67
6
75-100
79,83,89,97
4
  in the above table shows that from 1 to 25 numbers there are 9 prime numbers
similarly from 25 to 50 there are 6 prime numbers are there.
like wise from 51-75 there are 6 prime numbers and from 75 to 100 there are 4 prime numbers there.

by observing the above tables the the following questions can ask.

1 . What are the prime numbers between 20 and 50?
   Ans:prime numbers : 23,29.31,37,41,43,47
          since there are 7 prime numbers are there between 20 and 50.

2. How many prime numbers are between 30 and 50?
    Ans:prime numbers: 31,37,41,43,47
           since there are 5 prime numbers are there between 30 and 50.

3.What are the prime numbers between 70 and 100?
   Ans: prime numbers: 71,73,79,83,89,97
           there are six prime numbers are there between 70 and 100.
    
      

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