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2 years ago

Can someone please help me?

Mathematics

2 answers:

Ierofanga [76]2 years ago

5 0

Hello!

<h2>Answer:</h2>

The correct answer is option four, 27.

<h2>Explanation:</h2>

We know that a = 9.

Because the a is right next to the 7 and the 4, this indicates that it is being multiplied.

7a - 4a

Substitute for the 'a'.

= 7(9) - 4(9)

= 63 - 36

= 27

VikaD [51]2 years ago

4 0

Answer:

The answer is 27

Step-by-step explanation:

The reason being, you can solve this 2 ways.

1) Combine like terms, 7a-4a = 3a.

Now just substitute (a=9) into 3a.

3 * (9) = 27.

2) Or just substitute a = 9 into the original expression.

7 * (9) - 4 * (9)

= 63 - 36 = 27

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Answer:x

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3 years ago

Mr.Hollins determines that he gives away $800 each month. If he gives away 16% of his budget, how much is his overall budget?

oee [108]

$\frac{800}{x} = \frac{16\%}{100\%} \\ \frac{80000}{16} = \frac{16x}{16} \\ 5000 = x$

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3 years ago

There is a bag filled with 3 blue and 4 red marbles.

tresset_1 [31]

Using the hypergeometric distribution, it is found that there is a 0.4286 = 42.86% probability of getting 2 of the same colour.

The marbles are chosen without replacement, hence the <em>hypergeometric </em>distribution is used to solve this question.

<h3>What is the hypergeometric distribution formula?</h3>

The formula is:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}C_{N-k,n-x}}{C_{N,n}}$

$C_{n,x} = \frac{n!}{x!(n-x)!}$

The parameters are:

x is the number of successes.

N is the size of the population.

n is the size of the sample.

k is the total number of desired outcomes.

In this problem:

There is a total of 3 + 4 = 7 marbles, hence N = 7.

Of those, 3 are blue, hence k = 3.

2 marbles will be taken, hence n = 2.

The probability of getting 2 of the same colour is the sum of P(X = 0), which is both red, with P(X = 2), which is both blue, then:

$P(X = x) = h(x,N,n,k) = \frac{C_{k,x}C_{N-k,n-x}}{C_{N,n}}$

$P(X = 0) = h(0,7,2,3) = \frac{C_{3,0}C_{4,2}}{C_{7,2}} = 0.2857$

$P(X = 2) = h(2,7,2,3) = \frac{C_{3,2}C_{4,0}}{C_{7,2}} = 0.1429$

Hence:

$p = P(X = 0) + P(X = 2) = 0.2857 + 0.1429 = 0.4286$

0.4286 = 42.86% probability of getting 2 of the same colour.

You can learn more about the hypergeometric distribution at brainly.com/question/4818951

3 0

2 years ago

1)Sheyna drive to the lake and back. It took two hours less time to get there than it did to get back. The average speed on the

ipn [44]

Answer:

8 hours

Step-by-step explanation:

Given:

Sheyna drives to the lake with average speed of 60 mph and

$v_1 = 60\ mph$

Sheyna drives back from the lake with average speed of 36 mph

$v_2 = 36\ mph$

It took 2 hours less time to get there than it did to get back.

Let $t_1$ be the time taken to drive to lake.

Let $t_2$ be the time taken to drive back from lake.

$t_2-t_1 = 2$ hrs ..... (1)

To find:

Total time taken = ?

$t_1+t_2 = ?$

Solution:

Let D be the distance to lake.

Formula for time is given as:

$Time =\dfrac{Distance}{Speed }$

$t_1 = \dfrac{D}{60}\ hrs$

$t_2 = \dfrac{D}{36}\ hrs$

Putting in equation (1):

$\dfrac{D}{36}-\dfrac{D}{60} = 2\\\Rightarrow \dfrac{5D-3D}{180} = 2\\\Rightarrow \dfrac{2D}{180} = 2\\\Rightarrow D = 180\ miles$

So,

$t_1 = \dfrac{180}{60}\ hrs = 3 \ hrs$

$t_2 = \dfrac{180}{36}\ hrs = 5\ hrs$

So, the answer is:

$t_1+t_2 = \bold{8\ hrs}$

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3 years ago

Convert 150 meters per second into miles per day

statuscvo [17]

just divide it is simple bruh

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3 years ago