All categories

3 years ago

A caircular fountian has a circumference of 21 feet. Which expression can be used to find the diameter of the fountian in feet?

Mathematics

1 answer:

KiRa [710]3 years ago

5 0

Answer: $21 = 2\pi r$

Step-by-step explanation:

To find the circumference of a circle, you can use $2\pi r$ . You can set this equal to 21 (feet). The equation to solve at this point would be $21=2\pi r$ .

You might be interested in

The function f(x)=70n -400 models the profit of the instructor of a guitar class per month, where n is the number of students en

Ymorist [56]

Answer:

At least 6 students must be enrolled in the class for the instructor to make a profit.

At least 20 students must be enrolled in the class for the instructor to make $1,000 (or more) profit per month.

Step-by-step explanation:

The function $f(x)=70n -400$ models the profit of the instructor of a guitar class per month.

1. If the instructor makes a profit, then

$f(x)>0\\ \\70n-400>0\\ \\7n-40>0\\ \\7n>40\\ \\n>\dfrac{40}{7}\\ \\n>5\dfrac{5}{7}$

So, at least 6 students must be enrolled in the class for the instructor to make a profit.

2. If the instructor needs to make 1,000.00 profit per month, then

$f(x)\ge 1,000\\ \\70n-400\ge 1,000\\ \\7n-40\ge 100\\ \\7n\ge 140\\ \\n\ge \dfrac{140}{7}\\ \\n\ge 20$

So, at least 20 students must be enrolled in the class for the instructor to make $1,000 (or more) profit per month.

5 0

4 years ago

Marvin is painting three squares shaped like the one below if it takes him exactly 4 cans of paint to paint square 3 five cans o

noname [10]

Complete question:

Marvin is painting three squares shaped like the one below if it takes him exactly 4 cans of paint to paint square 3, five cans of paint to paint square 2 to how many cans of paint should he need to paint square one

Picture of squares is attached.

Answer:

9 cans of paint.

To paint square 1, he needs 9 cans of paint.

Step-by-step explanation:

Given that to paint square 3, four cans of paint are needed.

Therefore, let's take area of the square 3 as 4.

i.e a² = 4

Solving further, we have :

$a = \sqrt{4}$

a = 2

We can say, each side of square 3 = 2 units

To paint square 2, five cans of paint are needed. Let's take the area of 2 to be 5.

i.e b² = 5

Solving further, we have :

$b = \sqrt{5}$

We can say, each side of square 2 = $\sqrt{5}$ units

Using Pythagoras theorem, we have that the area of the square of a hypotenuse in a 90° angle is equal to the sum of the areas of the other two squares.

Therefore,

$h^2 = 2^2 + \sqrt{5}^2$

h² = 4 + 5

$h = \sqrt{9}$

h = 3 units.

We now know one side of the square 1 is 3 units.

Area of square 1 = 3²

Area = 9.

Therefore to paint square 1, he needs 9 cans of paint.

8 0

3 years ago

Students in Mr. Hill’s class were asked how many TV shows they watched last weekend. The results are shown on the line plot.

MAXImum [283]

Answer:

Step-by-step explanation:

Plz mark brainliest

8 0

3 years ago

What is reason #4?? <br> I’ll give best answer brainliest!

Svetradugi [14.3K]

Ok okookokkokk so u wouod do grab the 4 take the 24 add the 78 and their

6 0

4 years ago

In the last election, 60% of the class members voted. If the class has 120 members, how many members voted in the last election?

horrorfan [7]

That is a pretty apathetic class. now if you want to to this one, it is mental math. 60% is = to 50% +10%
50% of 120 is 60 and 10% of 12
60+12 is 72
the answer is 72 or A
hope this helps

6 0

4 years ago

Read 2 more answers

A caircular fountian has a circumference of 21 feet. Which expression can be used to find the diameter of the fountian in feet?​

A caircular fountian has a circumference of 21 feet. Which expression can be used to find the diameter of the fountian in feet?