Question 3
EasyOriginal questionHow many prime numbers lie between 30 and 60?
Show the answer and explanation
CorrectNot quiteAnswer B
Correct answer: B
Explanation
Test each odd number from 31 to 59 that does not end in 5.
Primes: 31, 37, 41, 43, 47, 53, 59.
That is 7 primes.
Worth noting
and look prime but are not; counting either gives 8.
- Concept
- Listing primes in a range
- Typical timeTypical
- 40 s
- Your timeYours
- —
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