Multiply the 3 times 4. Then do the same on the top.
Answer:
3 students
Step-by-step explanation:
There are 30 students in Mrs. Woodward’s class.
of the class has their own cell phone, so

students have their own cell phones.
of those 6 students are allowed to use social media. So,

students are allowed to use social media.
Answer: d
Step-by-step explanation:
Find the area of the rectangle.

Find the area of the base of the semicircle.

12 in would be the diameter, divide by 2 to get the radius.

Plug this into the formula.

Since we do not have a full circle but a semi one instead, we must divide our result by 2.

Add both areas.
180+56.52=236.52
Answer:
10
Step-by-step explanation:
Answer:
a. closed under addition and multiplication
b. not closed under addition but closed under multiplication.
c. not closed under addition and multiplication
d. closed under addition and multiplication
e. not closed under addition but closed under multiplication
Step-by-step explanation:
a.
Let A be a set of all integers divisible by 5.
Let
∈A such that 
Find 

So,
is divisible by 5.

So,
is divisible by 5.
Therefore, A is closed under addition and multiplication.
b.
Let A = { 2n +1 | n ∈ Z}
Let
∈A such that
where m, n ∈ Z.
Find 

So,
∉ A

So,
∈ A
Therefore, A is not closed under addition but A is closed under multiplication.
c.

Let
but
∉A
Also,
∉A
Therefore, A is not closed under addition and multiplication.
d.
Let A = { 17n: n∈Z}
Let
∈ A such that 
Find x + y and xy


So,
∈ A
Therefore, A is closed under addition and multiplication.
e.
Let A be the set of nonzero real numbers.
Let
∈ A such that 
Find x + y

So,
∈ A
Also, if x and y are two nonzero real numbers then xy is also a non-zero real number.
Therefore, A is not closed under addition but A is closed under multiplication.