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2 years ago

Beth has 120 pens in her pencil case , she give 20% to Federica. How many does she give her ?

Mathematics

2 answers:

vlabodo [156]2 years ago

5 0

Answer:

24 pencils

Step-by-step explanation:

(20 x 120)/100 = 24

True [87]2 years ago

4 0

Answer:

Step-by-step explanation:

you can just search it 20% of 120

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Tori sold 450 soft pretzels. If she sold them in groups of 15 soft pretzels, how many groups did she sell?. (Whole number only).

geniusboy [140]

Answer:

Step-by-step explanation:

450/15

4 0

3 years ago

Read 2 more answers

From a point A that is 8.20 m above level ground, the angle of elevation of the top of a building s 31 deg 20 min and the angle

Mariulka [41]

Answer:

30.11 meters ( approx )

Step-by-step explanation:

Let x be the distance of a point P ( lies on the building ) from the top of the building such that AP is perpendicular to the building and y be the distance of the building from point A, ( shown in the below diagram )

Given,

Point A is 8.20 m above level ground,

So, the height of the building = ( x + 8.20 ) meters,

Now, 1 degree = 60 minutes,

⇒ $1\text{ minute } =\frac{1}{60}\text{ degree }$

$20\text{ minutes }=\frac{20}{60}=\frac{1}{3}\text{ degree}$

$50\text{ minutes }=\frac{50}{60}=\frac{5}{6}\text{ degree}$

By the below diagram,

$tan ( 12^{\circ} 50') = \frac{8.20}{y}$

$tan(12+\frac{5}{6})^{\circ}=\frac{8.20}{y}$

$tan (\frac{77}{6})^{\circ}=\frac{8.20}{y}$

$\implies y=\frac{8.20}{tan (\frac{77}{6})^{\circ}}$

Now, again by the below diagram,

$tan (31^{\circ}20')=\frac{x}{y}$

$tan(31+\frac{1}{3})=\frac{x}{y}$

$\implies x=y\times tan(\frac{94}{3})=\frac{8.20}{tan (\frac{77}{6})^{\circ}}\times tan(\frac{94}{3})^{\circ}=21.9142943216\approx 21.91$

Hence, the height of the building = x + 8.20 = 30.11 meters (approx)

8 0

3 years ago

PLSS PLSS HELP ME!!! I WILL MARK U!

ziro4ka [17]

The answer is
h= -41.36

You first multiply -8.1(-0.4) and you get 3.24.
Then you subtract 3.24 - 44.6 to get h.

8 0

3 years ago

A^2(64a^2-3)/3=27-4a^2/4

frutty [35]

The answer is a = 3/4 = 0.75

First get rid of the paranthesis,
${a}^{2} (64 {a}^{2} - 3) = 64 {a}^{4} - 3 {a}^{2}$
Then set the denominators equal:
$\frac{ 256 {a}^{4} - 12 {a}^{2}}{12} = \frac{81 - 12 {a}^{2} }{12}$
Then remove the denominators and solve:
$256 {a}^{4} - 12 {a}^{2} = 81 - 12 {a}^{2}$
Eliminate -12a^2 by adding 12a^2 to both sides:
$256 {a}^{4} = 81$
Take the fourth root of them or take the square root twice:
$\sqrt[4]{256 {a}^{4} } = \sqrt[4]{81} \\ 4a = 3$
Divide both sides by 4:
$a = \frac{3}{4} = 0.75$

7 0

3 years ago

According to the World Health Organization (WHO) Child Growth Standards, the head circumference for boys at birth is normally di

Elena L [17]

Answer:

$z = \frac{X -\mu}{\sigma}$

This z score tell to us how many deviations we are below or above the mean for a given normal distribution.

For the case of Eddie we got:

$z= \frac{33.2-34.5}{1.3}= -1$

And for the case of Sue we got:

$z = \frac{32.7-33.9}{1.2}= -1$

So then for both cases we see that Eddie and Sue are 1 deviation below the true mean for each gender so then the best conclusion for this case would be:

C.They are the same size relative to other children of the same sex.

Step-by-step explanation:

We can define the random variable X as the head circumference for boys at birth and we know that the distribution for X is given by:

$X\sim N(\mu = 34.5, \sigma=1.3)$

Similarly we can define the random variable Y as the head circumference for boys at birth and we know that the distribution for Y is given by:

$Y\sim N(\mu = 33.9, \sigma=1.2)$

And we know that Eddie was born with 33.2 cm and Sue with 32.7 cm for the head circumference . Since we are interested to determine which child's head circumference is smaller relative to other children of the same sex, we can use the z score formula given by this formula:

$z = \frac{X -\mu}{\sigma}$

This z score tell to us how many deviations we are below or above the mean for a given normal distribution.

For the case of Eddie we got:

$z= \frac{33.2-34.5}{1.3}= -1$

And for the case of Sue we got:

$z = \frac{32.7-33.9}{1.2}= -1$

So then for both cases we see that Eddie and Sue are 1 deviation below the true mean for each gender so then the best conclusion for this case would be:

C.They are the same size relative to other children of the same sex.

5 0

3 years ago