Question

consider the sets below.
u = {x | x is a real number}
a = {x | x is an odd integer}
r = {x | x = 3, 7, 11, 27}
is r ⊂ a?
○ yes, because all the elements of set a are in set r
○ yes, because all the elements of set r are in set a
○ no, because each element in set a is not represented in set r
○ no, because each element in set r is not represented in set a

Explanation:

Step1: Define subset condition

A set $R$ is a subset of $A$ ($R \subset A$) if every element of $R$ is an element of $A$.

Step2: Check elements of R

Elements of $R$: $3, 7, 11, 27$. All are odd integers, so each is in $A$.

Step3: Match to correct option

The valid reasoning is that all elements of $R$ are in $A$.

Answer:

yes, because all the elements of set R are in set A