7. Marisa has $26 in her purse. She pays $5 for

PLEASE HELP ASAP

Archy [21]

I feel like its either b or c

3 0

4 years ago

Read 2 more answers

What is the answer in substiution y=2x-9 and y=3

ale4655 [162]

Answer:

x= -6

Step-by-step explanation:

7 0

2 years ago

Read 2 more answers

A student on a piano stool rotates freely with an angular speed of 2.85 rev/s . The student holds a 1.50 kg mass in each outstre

Vlad1618 [11]

Answer:r'=0.327 m

Step-by-step explanation:

Given

$N=2.85 rev/s$

angular velocity $\omega =2\pi N=17.90 rad/s$

mass of objects $m=1.5 kg$

distance of objects from stool $r_1=0.789 m$

Combined moment of inertia of stool and student $=5.53 kg.m^2$

Now student pull off his hands so as to increase its speed to 3.60 rev/s

$\omega _2=2\pi N_2$

$\omega _2=2\pi 3.6=22.62 rad/s$

Initial moment of inertia of two masses $I_0=2mr_^2$

$I_0=2\times 1.5\times (0.789)^2=1.867$

After Pulling off hands so that r' is the distance of masses from stool

$I_0'=2\times 1.5\times (r')^2$

Conserving angular momentum

$I_1\omega =I_2\omega _2$

$(5.53+1.867)\cdot 17.90=(5.53+I_o')\cdot 22.62$

$I_0'=1.397\times 0.791$

$I_0'=5.851$

$5.53+2\times 1.5\times (r')^2=5.851$

$2\times 1.5\times (r')^2=0.321$

$r'^2=0.107009$

$r'=0.327 m$

7 0

4 years ago

How to find x and y (the answer is x=25,y=20 but i couldn't get the answer

Yakvenalex [24]

How are you going to ask a question and answer it yourself w t f

7 0

3 years ago

Ksju [112]

Answer:

We conclude that the mean contents of cola bottles is more than or equal to the advertised 300 ml.

Step-by-step explanation:

We are given that Bottles of a popular cola drink are supposed to contain 300 ml of cola. The distribution of the contents is normal with standard deviation of 3 ml.

A student who suspects that the bottler is under-filling measures the contents of six bottles. The results are: 299.4, 297.7, 301.0, 298.9, 300.2, 297.0

Let $\mu$ = mean contents of cola bottles.

SO, Null Hypothesis, $H_0$ : $\mu \geq$ 300 ml {means that the mean contents of cola bottles is more than or equal to the advertised 300 ml}

Alternate Hypothesis, $H_A$ : $\mu$ < 300 ml {means that the mean contents of cola bottles is less than the advertised 300 ml}

The test statistics that will be used here is One-sample z test statistics as we know about the population standard deviation;

T.S. = $\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\bar X$ = sample mean contents of cola bottle = $\frac{\sum X}{n}$ = 299.03 ml

$\sigma$ = population standard deviation = 3 ml

n = sample of bottles = 6

So, test statistics = $\frac{299.03-300}{\frac{3}{\sqrt{6} } }$

= -0.792

Now at 5% significance level, the z table gives critical value of -1.6449 for left-tailed test. Since our test statistics is more than the critical value of z as -0.792 > -1.6449, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region due to which we fail to reject our null hypothesis.

Therefore, we conclude that the mean contents of cola bottles is more than or equal to the advertised 300 ml.

8 0

4 years ago