It is 7 because it has only two factors which are itself and one
hcf(10, 21) = 1 ⇒ 10 & 21 relatively prime hcf(12, 54) = 6 ⇒ 12 & 54 not relatively prime hcf(15, 27) = 3 ⇒ 15 & 27 not relatively prime hcf(21, 38) = 1 ⇒ 21 & 38 relatively prime
First few triangular numbers: 0, 1, 3, 6, 10, 15, 21, 28 Numbers that can be thrown with four dice: 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 Which of these numbers that are triangular: 6, 10, 15, 21 None of these is prime.
1, 4, 6, 8, 9, 12, 14, 15, 16, 18, 20, 21, 22...
x = 15 as 4*15+6 = 66 3*15+21 = 66 or an easier way to do it 4x - 3x = 1x 21 - 6 = 15 1x = 15
21: (3)+3=(6)+4=(10)+5=(15)+6=(21)
The greatest common factor of 6, 15 and 21 is 3. The prime factorization of 6 is 2*3 The prime factorization of 15 is 3*5 The prime factorization of 21 is 3*7 The GCF is then 3, as it is the only common factor.
It is 7 because it has only two factors which are itself and one
They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.
hcf(10, 21) = 1 ⇒ 10 & 21 relatively prime hcf(12, 54) = 6 ⇒ 12 & 54 not relatively prime hcf(15, 27) = 3 ⇒ 15 & 27 not relatively prime hcf(21, 38) = 1 ⇒ 21 & 38 relatively prime
First few triangular numbers: 0, 1, 3, 6, 10, 15, 21, 28 Numbers that can be thrown with four dice: 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 Which of these numbers that are triangular: 6, 10, 15, 21 None of these is prime.
1, 4, 6, 8, 9, 12, 14, 15, 16, 18, 20, 21, 22...
x = 15 as 4*15+6 = 66 3*15+21 = 66 or an easier way to do it 4x - 3x = 1x 21 - 6 = 15 1x = 15
21: (3)+3=(6)+4=(10)+5=(15)+6=(21)
21
1, 5, 9, 15, ? 1, 5(1+4), 9(5+4), 15(9+6), ?(15+?) since the addition of 4 is done 2 times, we can say that also will 6 ?=15+6 ?=21
The prime number is 7, because the only factors for 7 are 1 and 7.
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30