28
The sum of all prime numbers between 1 and 11 is 28.
There aren't any.
23
To find the GCF, you first need to break the numbers down into their prime factors: 28 = 2x2x7 20 = 2x2x5 40 = 2x2x2x5 The next step is to find any common prime factors. In this case, all three numbers have two 2s as prime factors. Multiply these and you get 4. Therefore the GCF of 28, 20 and 40 is 4.
Not all numbers between 20 and 28 are composite numbers. 23 is a prime number.
28
48
The prime numbers between 13 and 28 are 13 17 19 23 Multiples of 7 in that range include 14, 21 and 28.
All of them except 23 and 29 which are prime numbers
The sum of all prime numbers between 1 and 11 is 28.
They are: 21 22 24 25 26 27 28 because 23 and 29 are prime numbers
There aren't any.
There are 5 prime numbers between 8 and 28: 11 13 17 19 23
23
How many numbers are in 28
To find the GCF, you first need to break the numbers down into their prime factors: 28 = 2x2x7 20 = 2x2x5 40 = 2x2x2x5 The next step is to find any common prime factors. In this case, all three numbers have two 2s as prime factors. Multiply these and you get 4. Therefore the GCF of 28, 20 and 40 is 4.