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Olympiad
Easy
Number Theory
5–6
Is 91 a prime number?
91 é um número primo?
Answer options
A.
Yes
B.
No,
91
=
7
×
13
91 = 7 \times 13
91
=
7
×
13
C.
No,
91
=
3
×
31
91 = 3 \times 31
91
=
3
×
31
D.
No,
91
=
9
×
11
91 = 9 \times 11
91
=
9
×
11
Check Answer
Solution
91
=
7
×
13
91 = 7 \times 13
91
=
7
×
13
, so it is not prime.