Simplify. (7y)^2 Write your answer without parentheses.

Please give me the answers to all three I will mark u brilliant

elixir [45]

Answer:

First know the formula for the area of a circle;

Where 'π' represents pi(3.14 or 22/7), and 'r' stands for the radius being squared.

For the first problem, we can see that 12 is our diameter.

And to find the radius, we need to find 1/2 of the diameter (half of the diameter), so;

D/2 = R

Replace with actual values;

12/2 = 6, 6 is our radius.

Now we plug this into our formula:

A = π $r^{2}$

A = 3.14(6^2)

A = 3.14(36)

A = 113.04 centimetres is the area of the circle.

For the second problem, we can see that 18 is our diameter.

And to convert the diameter into the radius, we do what we did to the past problem, find 1/2 of the diameter.

So;

D/2 = R

18/2 = 9, 9 is our radius.

Now we plug this into our formula:

A = π $r^{2}$

A = 3.14(9^2)

A = 3.14(81)

A = 254.34 inches is the area for this circle.

For the third problem, we can see that our radius is already given, 5.

So now we just simply and easily plug this into our formula;

A = π $r^{2}$

A = 3.14(5^2)

A = 3.14(25)

A = 78.5 meters is the area for this circle.

4 0

1 year ago

If Karri takes a 7 question true false test and guess on every question, what is the

dusya [7]

Answer:

The probability that she gets all 7 questions correct is 0.0078.

Step-by-step explanation:

We are given that Karri takes a 7 question true-false test and guess on every question.

The above situation can be represented through binomial distribution;

$P(X = r) = \binom{n}{r} \times p^{r} \times (1-p)^{n-r} ; x = 0,1,2,3,........$

where, n = number of samples (trials) taken = 7 question

r = number of success = all 7 questions correct

p = probability of success which in our question is probability that

question is correct, i.e. p = 50%

Let X = Number of question that are correct

So, X ~ Binom(n = 7, p = 0.50)

Now, the probability that she gets all 7 questions correct is given by = P(X = 7)

P(X = 7) = $\binom{7}{7} \times 0.50^{7} \times (1-0.50)^{7-7}$

= $1 \times 0.50^{7} \times 0.50^{0}$

= 0.0078

6 0

3 years ago

Aunty Joan packs a packet of sweets to Alice and Olivia. Alice and Olivia share sweets in the ratio 7:3. Alice gives 3 sweets to

aivan3 [116]

Initially, Alice had 28 sweets and Olivia 12 sweets.

Step-by-step explanation:

First assume that Aunty Joan has x number sweets.

Alice and Olivia shared the x sweets in a ration of 7:3, this means

Alice had 7/10 x sweets and Olivia had 3/10 sweets.

Alice gives 3 sweets to Olivia, Alice will remain with ;

$\frac{7}{10} x-3$

Then the new ratio changes to 5:3 which means Alice will have 5/8 x number of sweets.

Equate the number of sweets for Alice in the two cases, which is

$\frac{5}{8}x=\frac{7}{10} x-3\\ \\\frac{7}{10} x-\frac{5}{8} x=3\\$

$\frac{56x-50x}{80} =3\\\\\\\frac{6}{80} x=3\\\\\\6x=80*3\\\\\\x=240/6\\\\x=40$

So there were 40 sweets at first

Using the ratio of 7:3 then

Alice had 7/10 *40 = 28 sweets

Olivia had 3/10*40= 12 sweets

Alice gave Olivia 3 sweets, so she will remain with 28-3 =25 sweets. Olivia will now have 15 sweets.The new ratio will be 25:15 simplified as 5:3.

Learn More

Ratio : brainly.com/question/11095585

Keywords : Ratio

#LearnwithBrainly

5 0

3 years ago

Jamil uses a 27 cm long wooden board to make a bookend.

Sholpan [36]

The answer would be 24.6 cm

5 0

2 years ago

Read 2 more answers

Use the formula you found in the previous question to find the degree of angle B if angle A = 35 and angle C = 90.

jok3333 [9.3K]

Answer: 55

Step-by-step explanation:

90+35=125

180 is the total degrees of an angle so 180-125= 55

6 0

3 years ago

Read 2 more answers

Simplify.(7y)^2Write your answer without parentheses.