Convert 7 0ver 2 to a decimal point

Does anyone know whoever answers i’ll mark brainlist

-Dominant- [34]

Answer:

(1,2)

Step-by-step explanation:

The solution to the system is where the two lines cross.

They cross at x=1 and y=2

(1,2)

8 0

3 years ago

The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to in

oksano4ka [1.4K]

Answer:

Null hypothesis: $\mu \leq 8000$

Alternative hypothesis: $\mu > 8000$

$z=\frac{8300-8000}{\frac{1200}{\sqrt{64}}}=2$

$p_v =P(Z>2)=0.0228$

Step-by-step explanation:

1) Data given and notation

$\bar X=8300$ represent the sample mean

$\sigma=1200$ represent the population standard deviation

$n=64$ sample size

$\mu_o =800$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

2) State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is higher than 8000, the system of hypothesis are :

Null hypothesis: $\mu \leq 8000$

Alternative hypothesis: $\mu > 8000$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

3) Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{8300-8000}{\frac{1200}{\sqrt{64}}}=2$

4) P-value

Since is a one-side upper test the p value would given by:

$p_v =P(Z>2)=0.0228$

5) Conclusion

If we compare the p value and the significance level assumed, for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the mean is significantly higher than $8000.

4 0

3 years ago

1/3(6x-12)=8(1/2x+1)-2

dlinn [17]

X = -5 is the answer I believe

8 0

3 years ago

Farmer Brown has 42 animals, which are cows and chickens. They have a total of 120 legs. Write a system of equations, show your

SCORPION-xisa [38]

Answer:

The system of equations is:

x + y = 42

4x + 2y = 120

And there are 24 chickens.

Step-by-step explanation:

We know that the total number of cows (x) plus the total number of chickens (y) is 42, because Farmer Brown has 42 animals.

We also know that cows (x) have 4 legs and so 4 times the number of cows is the number of cow legs. And chickens (y) have 2 legs, so the number of chickens times two represents the total chicken legs. The sum of 4x + 2y is 120 because there are 120 legs in total.

To solve the system of equations, first solve each equation for y.

In the first equation:

x + y = 42

Subtract x from both sides to isolate y.

y = 42 - x

Second equation:

4x + 2y = 120

Subtract 4x from both sides

2y = 120 - 4x

Divide both sides by 2

y = 60 - 2x

Now that the y's are isolated in both equation, you can put them into 1 equation. Where y = y:

y = 42 - x

y = 60 - 2x

42 - x = 60 - 2x

Add 2x to both sides

42 + x = 60

Subtract 42 from both sides

x = 18

Since x is the number of cows, we know that Farmer Brown has 18 cows.

Now we can substitute the x value into one of the equations:

y = 42 - x

y = 42 - (18)

y = 24

The number of chickens is represented by y, so there are 24 chickens.

3 0

3 years ago

Plastic cups come in packages of 24 and straws come in packages of 20, whats the smallest number of each that could be bought so

Aleks04 [339]

Answer:

120

Step-by-step explanation:

No. of plastic cups = 24

No. of straws =20

We need to find the smallest number of each that could be bought so that you had the same amount of cups and straws.

Prime factrisation of 24 = 2×3×2×2

Prime factorisation of 20 = 2×5×2

LCM = 120

Hence, the smallest number of each type will be 120.

6 0

3 years ago