12
17
9
11
Answer is Right!
Answer is Wrong!
The missing number is 11.
The numbers in the sequence are all prime numbers, except for 10, which is a composite number. 11 is the next prime number after 10.
A prime number is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number.