Random Mode Keyboard shortcut: Command/Ctrl + Shift + R
thumbnail

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
Rate:
Last updated: October 11, 2019
You have not attempted this quiz yet.
First submittedNovember 11, 2011
Times taken53,499
Average score68.0%
Rating4.49
0:45
Enter answer here
0
 / 25 guessed
The quiz is paused. You have remaining.
Scoring
You scored / = %
This beats or equals % of test takers also scored 100%
The average score is
Your high score is
Your fastest time is
Keep scrolling down for answers and more stats ...
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
+3
Level 10
Apr 10, 2016
Nailed it with approximately 1:20.0000000000000000 left :|
+3
Level 28
May 21, 2016
This should be 30 seconds
+13
Level 74
Nov 8, 2022
Feel free to complete it in 30 seconds :)
+6
Level 59
Apr 13, 2018
Funk whiz
+2
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
+10
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
+1
Level 49
Nov 9, 2022
thats pretty common knowledge tho
+2
Level 54
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 85
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
+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 :(
+1
Level 65
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 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.
+2
Level 68
Nov 9, 2023
You forgot 57, Grothendieck's prime number. 🤓
+1
Level 39
Nov 27, 2023
3*19