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average of prime numbers between 1 to 100

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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
Total no of prime numbers
25

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.

The following table shows the sum of prime numbers

Prime numbers
sum
1-25
2+3+5+7+11+13+17+19+23
100
26-50
29+31+37+41+43+47
228
51-75
53+59+71+73+61+67
384
75-100
79+83+89+97
348
Sum of the prime numbers
1060

so sum of the prime numbers from 1 to 100 is 1060.
Total no of prime numbers between 1 to 100 is 25.

Average=  sum of elements / no of elements
             = 1060/25
             =42.4
Since average of the prime numbers from 1 to 100 is 42.4


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