All categories

3 years ago

Whats the answer I am stuck

Mathematics

2 answers:

lubasha [3.4K]3 years ago

8 0

15/28 I believe is the answer

IrinaK [193]3 years ago

8 0

Answer:

3 $\frac{11}{28}$

Step-by-step explanation:

Note that

2 $\frac{1}{7}$ = 2 + $\frac{1}{7}$ and

1 $\frac{1}{4}$ = 1 + $\frac{1}{4}$

We can add the whole numbers together and the 2 fractions separately, that is

2 + 1 + $\frac{1}{7}$ + $\frac{1}{4}$

To add the fractions we require them to have a common denominator

The lowest common multiple of 7 and 4 is 28.

Multiply the numerator/denominator of the first fraction by 4

Multiply the numerator/denominator of the second fraction by 7

= 3 + $\frac{1(4)}{7(4)}$ + $\frac{1(7)}{4(7)}$

= 3 + $\frac{4}{28}$ + $\frac{7}{28}$

= 3 + $\frac{4+7}{28}$

= 3 + $\frac{11}{28}$

= 3 $\frac{11}{28}$

You might be interested in

In 1945. an organization surveyed 1100 adults and asked. "Are you a total abstainer from, or do you on occasion consume, alcohol

oee [108]

Answer:

$n_1 p_1 =1100*0.31=341 \geq 10$

$n_1 (1- p_1) =1100*(1-0.31)=759 \geq 10$

$n_2 p_2 =1100*0.33=363 \geq 10$

$n_2(1- p_2) =1100*(1-0.33)=737 \geq 10$

The data come from a population that is normally distributed.

The samples are independent

$z=\frac{0.31-0.33}{\sqrt{0.32(1-0.32)(\frac{1}{1100}+\frac{1}{1100})}}=-0.47$

Since is a two sided test the p value would be:

$p_v =2*P(Z$

If the population proportions are equal one would expect a sample difference proportion greater than the absolute value of the 64 observed in about out of 100 repetitions of this experiment.

Step-by-step explanation:

1) Data given and notation

$X_{1}=341$ represent the number of people indicated that they were total abstainers In a recent survey

$X_{2}=363$ represent the number of people indicated that they were total abstainers In a 1945 survey,

$n_{1}=1100$ sample 1

$n_{2}=1100$ sample2

$p_{1}=\frac{341}{1100}=0.31$ represent the proportion of people indicated that they were total abstainers In a recent survey

$p_{2}=\frac{363}{1100}=0.33$ represent the proportion of people indicated that they were total abstainers In a 1945 survey,

z would represent the statistic (variable of interest)

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

$\alpha=0.05$ significance level given

$n_1 p_1 =1100*0.31=341 \geq 10$

$n_1 (1- p_1) =1100*(1-0.31)=759 \geq 10$

$n_2 p_2 =1100*0.33=363 \geq 10$

$n_2(1- p_2) =1100*(1-0.33)=737 \geq 10$

The data come from a population that is normally distributed.

The samples are independent

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if is there is a difference in the two proportions of interest, the system of hypothesis would be:

Null hypothesis: $p_{1} - p_{2}=0$

Alternative hypothesis: $p_{1} - p_{2} \neq 0$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{361+343}1100+1100}=0.32$

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.31-0.33}{\sqrt{0.32(1-0.32)(\frac{1}{1100}+\frac{1}{1100})}}=-0.469$

Statistical decision

Since is a two sided test the p value would be:

$p_v =2*P(Z$

Comparing the p value with the significance level given $\alpha=0.1$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't say that we have a significant differences between the two proportions.

If the population proportions are equal one would expect a sample difference proportion greater than the absolute value of the 64 observed in about out of 100 repetitions of this experiment.

7 0

2 years ago

The edges of a shoebox are measured to be 11.3 cm, 18.9 cm, and 29 cm. Determine the volume of the box retaining the proper numb

puteri [66]

The volume (V) is given in terms of length (L), width (W), and height (H) by the formula ...

... V = LWH

Substituting your dimensions, you have

... V = (11.3 cm)·(18.9 cm)·(29 cm) = 6193.53 cm³ ≈ 6200 cm³

_____

The factor 29 cm has 2 significant digits, so that is the precision required of the answer. It could also be written with less ambiguity as to precision as 6.2 L. (Trailing zeros to the left of the decimal point are always ambiguous when it comes to significant digits.)

7 0

2 years ago

kondaur [170]

A digit is a number in one of the places, so for example the number 54 has two digits; a tens place digit (5) and a ones place digit (4).

Say the mystery number is a two digit number = xy
* that's not x times y but two side by side digits.

Info given:
the sum of the digits of a two-digit number is 6
x + y = 6 
if the digits are reversed, yx the difference between the new number and the original number is 18.

**To obtain the number from digits you must multiply by the place and add the digits up. (Example: 54 = 10(5) + 1(4))

Original number = 10x + y
Reversed/New number = 10y + x

Difference:
10y + x - (10x + y) = 18
9y - 9x = 18
9(y - x) = 18
y - x = 18/9
y - x = 2

Now we have two equations in two variables
y - x = 2
x + y = 6

Re-write one in terms of one variable for substitution.
y = 2 + x
sub in to the other equation to combine them.
x + (2 + x) = 6
2x + 2 = 6
2x = 6 - 2
2x = 4
x = 2

That's the tens digit for the original number. Plug this value into either of the equations to obtain y, the ones digit.

2 + y = 6
y = 4

number "xy" = 24

4 0

2 years ago

School... are you aloud to skip school!!

kirza4 [7]

it depends :/ like it depends on the class n shi but never ever skip 2 periods inna row cuz then

u too susss. also yes

writing random exp.

for points so dont come at me

8 0

3 years ago

Read 2 more answers

What is the slope of the line that contains the points (-1, 8) and (2, -4)

Reptile [31]

Answer:

+5 is the slope

Step-by-step explanation:

4 0

3 years ago