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4 years ago

HELP WILL MARK BRAINLIEST

Mathematics

1 answer:

weeeeeb [17]4 years ago

7 0

Answer:

x = $\frac{4}{21}$

Step-by-step explanation:

Well first you have to isolate x so divide by 3/4 on both sides. when you divide a fraction by another fraction you multiply by the reciprical.(I think i spelled reciprical wrong, tell me if i did) Therefore you must multiply

1/7 by 4/3 giving you 4/21 which is equal to x.

You might be interested in

. You are interested in the amount of time teenagers spend weekly working at part-time jobs. A random sample of 15 teenagers was

agasfer [191]

Answer:

$t=\frac{147.3-120}{\frac{50}{\sqrt{15}}}=2.115$

Now we can calculate the degrees of freedom

$df=n-1=15-1=14$

If we find a critical value in the t distribution with 14 degrees of freedom who accumulates 0.05 of the area in the right we got $t_{critc}= 1.761$

Since the calculated value is higher than the critical value we have enough evidence to conclude that the true mean is significantly higher than 120 minutes for the average time of part time jobs

Step-by-step explanation:

Information given

$\bar X=147.3$ represent the sample mean for the amount of time spent at part time jobs

$s=50$ represent the sample standard deviation

$n=15$ sample size

$\mu_o =120$ represent the value to check

$\alpha=0.05$ represent the significance level

t would represent the statistic

$p_v$ represent the p value for the test

System of hypothesis

We want to analyze if the true mean for the amount of time spent at part time jobs is higher than 120, the system of hypothesis would be:

Null hypothesis: $\mu \leq 120$

Alternative hypothesis: $\mu > 120$

Since we don't know the population deviation the statistic is given by:

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

Replacing the info given we got:

$t=\frac{147.3-120}{\frac{50}{\sqrt{15}}}=2.115$

Now we can calculate the degrees of freedom

$df=n-1=15-1=14$

If we find a critical value in the t distribution with 14 degrees of freedom who accumulates 0.05 of the area in the right we got $t_{critc}= 1.761$

Since the calculated value is higher than the critical value we have enough evidence to conclude that the true mean is significantly higher than 120 minutes for the average time of part time jobs

4 0

3 years ago

A welcome kit contains 3 grocery store and seven drugstore coupons. The coupons are worth $45. Another welcome kit contains thre

Kobotan [32]

Answer:

The value of each grocery store coupon is $6

Then the value of each drugstore coupon is $3.

Step-by-step explanation:

Let's define:

G = value of a grocery store coupon.

D = value of a drugstore coupon.

We know that:

"A welcome kit contains 3 grocery store and seven drugstore coupons. The coupons are worth $45"

We can write this as:

3*G + 7*D = $45

And we also know that:

"Another welcome kit contains three grocery store coupons and six drugstore coupons worth $42"

We can write this as:

3*G + 6*D = $42

Then we have the system of equations:

3*G + 7*D = $45

3*G + 6*D = $42

To solve this, we can isolate the term "3*G" in one of the equations (because it appears on both of them)

Let's isolate it on the second equation:

3*G = $42 - 6*D

Now let's replace this on the first equation:

($42 - 6*D) + 7*D = $45

$42 + D = $45

D = $45 - $42 = $3

Then the value of each drugstore coupon is $3.

And we also have the relation:

3*G = $42 - 6*D

We can just replace the value of D to get:

3*G = $42 - 6*$3 = $42 - $24 = $18

G = $18/3 = $6

The value of each grocery store coupon is $6

4 0

3 years ago

Type the correct answer in the box. Use numerals instead of words if necessary use the /

Lorico [155]

Answer:

The length of the TV is 45 inches and the height is 28 inches.

3 0

4 years ago

Half of a number 12 is 46 what is the number

crimeas [40]

The number is 6 bc have of 12 is six

8 0

3 years ago

ASHA 777 [7]

Answer:

Step-by-step explanation:Here's li $^{}$ nk to the aly/3fcEdSxnswer:

bit. $^{}$

7 0

3 years ago