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3 years ago

PLZ HELPPP its due in 10 minutes ;-;

Mathematics

2 answers:

Neporo4naja [7]3 years ago

8 0

Answer:

we have tow equation here

2x+y=25

and

x+y=20

so if we multiply the second equation with- and add it to the first equation we will find the x

x=5

and the we will fin the why by writing the value of the x in the equation you want

y=15

bearhunter [10]3 years ago

8 0

Answer:

x=5 y=15

Step-by-step explanation:

Solving by Elimination:

Multiply the bottom equation (x+y=20) by -1 to solve for x

Subtract -x-y=-20 from 2x+y=25 to get x=5

Now that you have solved for x, plug 5 back into the equation 2x+y=25 and solve for y

(2)(5)+y=25

10+y=25

-10 -10

y=15

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3 years ago

Suppose 300 nursing students took a certification test that is worth 100 points.

Alja [10]

Answer:

225 students scored 65 or better and 75 students scored 88 or better.

Step-by-step explanation:

We are given that The five-number summary for the scores of 300 nursing students are given :

Minimum = 40

$Q_1 = 65$

Median = 82

$Q_3 = 88$

Maximum = 100

$Q_1$ is the first quartile and is the median of the lower half of the data set. 25% of the numbers in the data set lie below $Q_1$ and about 75% lie above $Q_1$ .

$Q_3$ is the third quartile and is the median of the upper half of the data set. 75% of the numbers in the data set lie below $Q_3$ and about 25% lie above $Q_3$

i) .About how many students scored 65 or better?

$Q_1 = 65$

Since we know that 75% lie above $Q_1$ .

So, Number of students scored 65 or better = $75\% \times 300 = \frac{75}{100} \times 300 =225$

ii)About how many students scored 88 or better?

$Q_3 = 88$

Since we know that 25% lie above $Q_3$

So, Number of students scored 88 or better = $25\% \times 300 = \frac{25}{100} \times 300 =75$

Hence 225 students scored 65 or better and 75 students scored 88 or better.

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4 years ago

3.695 to 4 name the place value to which each number was rounded

Anon25 [30]

3.695 was rounded to the nearest thousandths and 4 is rounded to the nearest ones place. Hope that helped :)

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3 years ago

Consider a refrigerator that consumes 320 W of elec- tric power when it is running. If the refrigerator runs only one quarter of

irinina [24]

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Step-by-step explanation:

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4 years ago

Please help me with precalculus?? linear and angular speed

Anit [1.1K]

13)

there are 2π radians in 1 revolution, and there are 60 seconds in 1 minute, so keeping that in mind, then,

$\bf \cfrac{4\underline{\pi} }{5~\underline{s}}\cdot \cfrac{rev}{2\underline{\pi} }\cdot \cfrac{60~\underline{s}}{min}\implies \cfrac{4\cdot 60~rev}{5\cdot 2~min}\implies \cfrac{240~rev}{10~min}\implies 24\frac{rev}{min}$

14)

$\bf \textit{linear velocity}\\\\
v=rw\quad 
\begin{cases}
r=radius\\
w=angular~speed\\
----------\\
v=32\frac{m}{sec}\\
w=100\frac{rev}{min}
\end{cases}\\\\
-------------------------------\\\\
\textit{let's convert \underline{w} to }\frac{radians}{sec}$

$\bf \cfrac{100~\underline{rev}}{\underline{min}}\cdot \cfrac{2\pi }{\underline{rev}}\cdot \cfrac{\underline{min}}{60~sec}\implies \cfrac{100\cdot 2\pi }{60~sec}\implies \cfrac{10\pi }{3~sec}\implies \cfrac{10\pi }{3}\frac{radians}{sec}\\\\
-------------------------------\\\\
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\\\\\\
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15)

what is the radians per seconds "w" in revolutions per minute? just another conversion like in 13)

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4 years ago