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prime number-2

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In previous post we learned how to write prime numbers.
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
uestions   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.

some times questions are like this.
what is the sum of prime numbers between 1 to  25?
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

so sum of the prime numbers from 1 to 25 is 100.
similarly the sum of prime numbers from 75 to 100 is 348

till now we learned prime numbers between 1 to 100.
now we will see the prime numbers from 1 to 1000

23571113171923293137
4143475359616771737983
8997101103107109113127131137139149
151157163167173179181191193197199
211223227229233239241251257263269271
277281283293307311313317331337347
349353359367373379383389397401409419
421431433439443449457461463467479
487491499503509521523541547557563569
571577587593599601607613617619631
641643647653659661673677683691701709
719727733739743751757761769773787
797809811821823827829839853857859863
877881883887907911919929937941947
953967971977983991997


By seeing above the table of prime numbers from 1 to 1000 we can observe that 168 prime numbers are there.

by seeing the below table we can observe how the prime numbers are distributed.

1-100
2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97
25
101-200
101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
21
201-300
211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293
16
301-400
307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397
16
401-500
401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499
17
501-600
503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599
14
601-700
601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691
16
701-800
701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797
14
801-900
809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887,
15
901-1000
907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997
14



there are 21 prime numbers are there between the 101 to 200. similarly we can observe other numbers in the above table. 














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