20 grams of KCl to moles of

vesna_86 [32]

For E the answer is 2. Because the square of 1 is one and 9 is three. And 2 to the square root of two which would be 2 time 2= 4

5 0

2 years ago

If a car factory checks 360 cars and 8 of them have defects, how many will have defects out of 1260?

viktelen [127]

You should expect 28 defected cars.

3 0

3 years ago

Write a formula that will yield the nth term of the sequence: 3,-2,-7,-12

RUDIKE [14]

Answer:

-5n + 8

Step-by-step explanation:

1. What is the difference?

The sequence goes down by 5. This means that the formula will have -5n in it.

2. Work out the term before the first term.

The first term is 3, and we know that the sequence goes up by 5. So, to get the term before 3 we would add 5.

3 + 5 = 8 Remember, this is positive 8. (+8)

3. Put that term at the end of the equation.

We have -5n already and we just worked out the term before the first one which is positive 8 - so put that at the end of the equation.

-5n + 8 This is our answer!

Just to prove it works:

Substitute: n = term

Lets see if we can get the 3rd term which is -7. (n = 3)

-5(3) + 8

-15 + 8 = -7

See, it works!

8 0

3 years ago

A study of pollutants showed that certain industrial emissions should not exceed 2.3 parts per million. You believe a particular

Musya8 [376]

Answer:

$t=\frac{3.3-2.3}{\frac{0.4}{\sqrt{9}}}=7.5$

The degrees of freedom are given by:

$df=n-1=9-1=8$

And the p value would be:

$p_v =P(t_{(8)}>7.5)=0.0000346$

Since the p value is lower than the significance level we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 2.3 ppm the safe limit

Step-by-step explanation:

Information provided

$\bar X=3.3$ represent the sample mean in ppm

$s=0.4$ represent the sample standard deviation

$n=9$ sample size

$\mu_o =2.3$ represent the value to verify

$\alpha=0.05$ represent the significance level

t would represent the statistic

$p_v$ represent the p value

System of hypothesis

We want to verify if the true mean is higher than 2,3 ppm, the system of hypothesis would be:

Null hypothesis: $\mu \leq 2.3$

Alternative hypothesis: $\mu > 2.3$

The statistic for this case is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

Replacing the info given we got:

$t=\frac{3.3-2.3}{\frac{0.4}{\sqrt{9}}}=7.5$

The degrees of freedom are given by:

$df=n-1=9-1=8$

And the p value would be:

$p_v =P(t_{(8)}>7.5)=0.0000346$

Since the p value is lower than the significance level we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 2.3 ppm the safe limit

6 0

3 years ago

Factor completely 3x^2+9x-3 3(x^2+3) 3(x^2+3-1) 3x(x^2+3x-1) prime

Firdavs [7]

Answer:

Answer from the answer data to choose from

Factor completely

$3\left(x+\dfrac{3-\sqrt{13}}{2}\right)\left(x+\dfrac{3+\sqrt{13}}{2}\right)$

Step-by-step explanation:

$3x^2+9x-3=(3)(x^2)+(3)(3x)-(3)(1)\\\\=(3)(x^2+3x-1)\\\\\text{For}\ x^2+3x-1\ \text{use the quadratic formula}\\\\x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x^2+3x-1\to a=1,\ b=3,\ c=-1\\\\x=\dfrac{-3\pm\sqrt{3^2-4(1)(-1)}}{2(1)}=\dfrac{-3\pm\sqrt{9+4}}{2}=\dfrac{-3\pm\sqrt{13}}{2}=-\dfrac{3\pm\sqrt{13}}{2}\\\\3x^2+9x-3=3\left(x+\dfrac{3-\sqrt{13}}{2}\right)\left(x+\dfrac{3+\sqrt{13}}{2}\right)$

4 0

3 years ago