All categories

4 years ago

What to do ?? i need help please asap one question left

Mathematics

1 answer:

maks197457 [2]4 years ago

3 0

Answer: $(x^{\frac{2}{7}})(x^{\frac{3}{5}})$

Step-by-step explanation:

If you took the nth root of x, it is the same as raising x to the power of 1/n. Therefore:

$\sqrt[7]{x^{2} } = (x^{2} )^{1/7} = (x^{\frac{2}{7}})\\\sqrt[5]{x^{3} } = (x^{3} )^{1/5} = (x^{\frac{3}{5}})$

And multiply:

$(x^{\frac{2}{7}})(x^{\frac{3}{5}})$

You might be interested in

Two independent samples of sizes 20 and 30 are randomly selected from two normally distributed populations. Assume that the popu

aleksley [76]

Answer:

b. Student-t with 48 degrees of freedom

Step-by-step explanation:

For this case we need to use a Two Sample t Test: equal variances.

Assumptions

When running a two-sample equal-variance t-test, the basic assumptions are "that the distributions of the two populations are normal, and that the variances of the two distributions are the same".

Let $\bar x$ and $\bar y$ be the sample means of two sets of data of size $n_x$ and $n_y$ respectively. We assume that the distribution's of x and y are:

$x \sim N(\mu_x ,\sigma_x =\sigma)$

$y \sim N(\mu_y ,\sigma_y=\sigma)$

Both are normally distributed but without the variance equal for both populations.

The system of hypothesis can be:

Null hypothesis: $\mu_x =\mu_y$

Alternative hypothesis: $\mu_x \neq \mu_y$

We can define the following random variable:

$t=\frac{(\bar x -\bar y)-(\mu_x -\mu_y)}{s\sqrt{\frac{1}{n_x}+\frac{1}{n_y}}}$

The random variable t is distributed $t \sim t_{n_x +n_y -2}$ , with the degrees of freedom $df=n_x +n_y -2= 20+30-2=48$

And the pooled variance can be founded with the following formula:

$s^2=\frac{(n_x -1)s_x^2 +(n_y-1)s_y^2}{n_x +n_y -2}$

So on this case the best answer would be :

b. Student-t with 48 degrees of freedom

5 0

3 years ago

For the past three months Grace used her cell phone for 43 minutes 62 minutes and 57 minutes how many minutes would you have to

RSB [31]

Answer:

Grace should use her phone for 58 minutes to maintain an average of 55 minutes.

Step-by-step explanation:

Usage of first month = 43 minutes

Second month = 62 minutes

Third Minutes = 57 minutes

Let, the usage of fourth month = k minutes

Mean of the data = 5 minutes

Now, Average of a Data = $\frac{\textrm{Sumof observations}}{\textrm{Total number of observations}}$

⇒ $55 = \frac{43 + 62 + 57 + k}{4}$

or, 55 x 4 = 162 + k

⇒ 220 - 162 = k

or, k = 58 minutes

So, Grace should use her phone for 58 minutes to maintain an average of 55 minutes.

5 0

3 years ago

If a 32 ft rope is cut into two sections with one section 7 times as log as the other section, how long is teh shorter piece?

steposvetlana [31]

The total length of the rope = 32 ft
It is cut into two sections, say x and y
But one section is seven times the other, say y=7x (shorter section being x)
Solving for x

x+y =32
x+7x = 32
8x=32
x=32/8 = 4 ft.
Therefore, the shorter piece is 4 ft long.

5 0

3 years ago

Simplify the following expresion by combining like terms 6y-23-y+72

Maurinko [17]

Simplest form would be, 5y-23+72 then it would be 5y+49

7 0

3 years ago

What is the answer for what x equals

Yuliya22 [10]

Answer:

Im not good at shapes and geometry but what i can tell u is that x = 1 so whenever u get ur area or whatever you can multiply it by one and thats what your answer is.

Step-by-step explanation:

8 0

3 years ago