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3 years ago

11

Xiomara bought 3 books that each cost the same amount and a magazine for a total of $27. If the magazine cost $3, then how much

was each book? Write an equation and solve.

2 answers:

pychu [463]3 years ago

7 0

$7 is 1/6 of 3/7 of Bella's money, so she had $98 to start with. 4/7 of 98 is $56, as you figured.

The dictionary and the books cost 56

d+3b = 56

3/8 d = 1/2 * 3b

so, 3d = 12b

4b + 3b = 56

b = 8

check:

3 books cost 24

dictionary cost 32

3/8(32) = 1/2(24)

12=12

skelet666 [1.2K]3 years ago

4 0

Answer:$8

Step-by-step explanation:

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Answer:

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3 years ago

Which statement is true about the function f(x)=-√-x

Harrizon [31]

Answer: D.The domain and range of the function are the same.

Step-by-step explanation: Given function f(x)=-√-x.

The given function is a square root function and we have minus sign in front of x inside square root.

A square root always defined for positive values or 0.

In order to get a positive number or 0 inside square root, let us solve the inequality:

$-x\geq 0$

On dividing both sides by -1, the inequality sign would get flip and we get

<h3>Domain: $x \leq 0.$ </h3>

We can see that we have a negative sign in front of square root. So, the value of f(x) would be always a negative number or 0.

<h3>Therefore, range would also be : $x \leq 0.$ .</h3><h3>Therefore, correct option is D option.</h3>

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3 years ago

A particle, initially at rest, moves along the x-axis such that its acceleration at time t > 0 is given by a(t) = 6cos(t). At

Rom4ik [11]

a. By the fundamental theorem of calculus, the velocity function is

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Then the position function is

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with $x(0)=6$ , so

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b. The particle is at rest whenever $v(t)=0$ ; this happens for

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3 0

3 years ago

Any help? Thanks in advance!

fgiga [73]

Answer:

c

Step-by-step explanation:

$2^{4}$ =16

$\sqrt[3]{16}$

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3 years ago

What is the z-score of a newborn who weighs 4,000 g?.

vagabundo [1.1K]

The z-score of the considered newborn having 4,000 g weight is $\dfrac{4000 - \mu}{\sigma}$

<h3>How to get the z scores?</h3>

If we've got a normal distribution, then we can convert it to standard normal distribution and its values will give us the z score.

If we have

$X \sim N(\mu, \sigma)$

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then it can be converted to standard normal distribution as

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(Know the fact that in continuous distribution, probability of a single point is 0, so we can write

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Also, know that if we look for Z = z in z tables, the p value we get is

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Thus, for them, we can consider variables in place of their actual values.

Let we have:

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Thus, the z-score of the considered newborn having 4,000 g weight is $\dfrac{4000 - \mu}{\sigma}$

Learn more about z-scores here:

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2 years ago