which of the following group of numbers are all prime numbers a.2,5,15,19 b.7,17,29,49 c.3,11,23,31 d.2,3,5,9,
antoniya [11.8K]
Prime numbers are those that cannot be divided by another number (other than themselves and 1). In other words, prime numbers have factors of themselves and 1.
For example, 3 is a prime number because its only factors are 3 and 1.
6 is not a prime number because it can be factored to 3*2.
Therefore, the correct answer is c. 3,11,23,31
Answer:
Step-by-step explanation:
1. Since 9 pages in 3 hours were read, we would find the greatest common factor (GCF) of both numbers, which is 3. So you do 9 divided by 3 (3) and 3 divided by 3 (1) which leaves you with the unit rate 3/1 or 3 pgs. p/ hr.
2. 20/4. The GCF of 20 and 4 is 4. So 20 divided by 4 is 5 and 4 divided by 4 is 1. Therefore leaving you with the unit rate 5/1 or 5 lb. p/ $.
3. 60/2. The GCF of 60 and 2 is 2. 60 divided by 2 is 30. 2 divided by 2 is 1. So the manatee can surface again in 30 seconds. 30/1 or 30 b. p/ sec.
Hope I helped! :)
Answer:
C
Step-by-step explanation:
609/504 = 1.208333333
58/48 = 1.208333333
They are proportional since they divide to the same number.
