Which one of the following groups of numbers includes all prime numbers? A. 7, 17, 63, 67 B. 3, 11, 23, 31 C. 1, 3, 11, 23 D. 2,
olganol [36]
The prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.
A.
7 - is a prime number
17 - is a prime number
63 - is not a prime number because 63 = 3 × 21
B.
3 - is a prime number
11 - is a prime number
23 - is a prime number
31 - is a prime number
C.
1 - is not a prime number
D.
2 - is a prime number
3 - is a prime number
5 - is a prime number
15 - is not a prime number because 15 = 3 × 5
15:25 = 3:5
simply divide 15 and 25 both by 5 to get 3:5.
What do u need help with. City a is -15 and city b is +15 or just 15
28:35
Those are divisible by 7 so divide both sides by seven
the answer is 4:5
