Between 11 and 21: 12, 14, 15, 16, 18 and 20.
It is 16. This is because there are five numbers between 11 and 16, and there are five numbers between 16 and 21 :]
21 and 22 are consecutive composite numbers.
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A number is divisible by 7 if it is a multiple of 7, so to figure it out, start listing multiples of 7. 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, ... On this list there are 11 numbers that are between 11 and 90. The answer is 11 numbers between 11 and 90 are divisible by 7.
All the numbers are composite except the ones in bold: 18 19 20 21 22 23 24 25.
composite numbers between 11 and 21:12 14 15 16 18
The composite numbers between 21 and 31 are: 21 22 24 25 26 27 28 30
There are 3 composite numbers between 20 and 25. They are 21, 22, and 24.
12, 14, 15, 16, 18, 20, 21, 22
The composite numbers between 20 and 30 are 21, 22, 24, 25, 26, 27, and 28.
The composite numbers between 20 and 25 are 21, 22, and 24. 23 is the only prime number between 20 and 25.
4, 21
The composite numbers between 20 and 30 are: 20 21 22 24 25 26 27 28 30
No, they are three numbers, not one. 21 is composite.
It is 16. This is because there are five numbers between 11 and 16, and there are five numbers between 16 and 21 :]
Prime numbers: 11, 13, 17, 19, 23, 29 Composite numbers: 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30
20, 21, 22, 24, 25