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Prime Numbers 1-100

There are 25 prime numbers that are less than one hundred. How many can you name in 45 seconds?
Quiz by johnnyaitch
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Last updated: October 11, 2019
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First submittedNovember 11, 2011
Times taken75,570
Average score68.0%
Rating4.45
0:45
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Prime #
2
3
5
7
11
Prime #
13
17
19
23
29
Prime #
31
37
41
43
47
Prime #
53
59
61
67
71
Prime #
73
79
83
89
97
25 Comments
+4
Level 10
Apr 10, 2016
Nailed it with approximately 1:20.0000000000000000 left :|
+4
Level 28
May 21, 2016
This should be 30 seconds
+25
Level 74
Nov 8, 2022
Feel free to complete it in 30 seconds :)
+7
Level 59
Apr 13, 2018
Funk whiz
+3
Level 50
Apr 30, 2022
guys fun fact:Any number above two that is a even number is a composite number meaning it’s not a prime number
+12
Level 77
Oct 25, 2022
Fun fact: because half of all numbers are divisible by 2, we know that less than half of all numbers are prime. We also know that 1/3 of the remaining 1/2 are not prime because they are divisible by 3, so 1/2 + 1/6 of numbers are not prime-which is 2/3. We also know that numbers divisible by 5 aren't prime! So of the remaining 1/3 potential prime numbers, 1/5 are not prime, meaning 1/3*1/5 = 1/15. 1/15+2/3 = 11/15...
+1
Level 50
Nov 8, 2022
Still though, crossing almost half is decent
+2
Level 49
Nov 9, 2022
thats pretty common knowledge tho
+3
Level 55
Nov 9, 2022
5 is also a factor of 10 so no prime number (except 5 itself) can ever end with 5. Therefore all prime numbers larger than 5 end with 1,3,7 or 9.
+1
Level 87
Oct 25, 2022
Great quiz! Could probably be done in less than 30 seconds.
+2
Level 56
Nov 8, 2022
I barely did it in under 30 seconds first try. But I think this isn't necessarily a speed quiz, so 45 seconds is more than doable
+2
Level 57
May 7, 2024
It can be done in 10 seconds if you've just memorized them. I haven't so I couldn't do it in less than 30 seconds on my first try, but ezpz on second try..
+1
Level 22
Nov 9, 2022
i tried this 20 times and i finally got it cause idk prime numbers
+1
Level 35
Nov 11, 2022
bro america taught me that all composite numbers were prime numbers im dead :(
+6
Level 66
Oct 23, 2023
i think that maybe, just maybe, you simply weren't paying attention...

or your teacher was one of THOSE teachers...

+1
Level 43
May 7, 2024
i dont think that was america
+1
Level 23
Nov 13, 2022
Wow! I got them all in 23 seconds!
+2
Level 81
Mar 30, 2023
Fun fact: 0% percent of integers are prime numbers.
+1
Level 72
May 7, 2024
Simultaneously, there are an infinite number of primes.
+2
Level 68
Nov 9, 2023
You forgot 57, Grothendieck's prime number. 🤓
+2
Level 39
Nov 27, 2023
3*19
+2
Level 72
May 7, 2024
Yes, that's the joke. A Grothendieck prime (namely 57) is a number that looks like it's prime, but isn't.
+1
Level 21
May 7, 2024
I count prime numbers to keep calm
+1
Level 35
May 7, 2024
lmao what is that picture
+1
Level 16
May 7, 2024
You have to make the time longer. I just got 10 in that time.