Select the statement which best fits the justification for the step in Line 5.

Devin is on his school's swim team. During his 2-week winter break, he swims 30 laps each week to stay in shape. If each lap is

tamaranim1 [39]

I think... 1500

Step-by-step explanation:

multiply 30 and 25 then times 750 as your answer by 2 to get 1500

7 0

3 years ago

40 PTS if u do this correctly! Algebra 1 Do #'s 4,5,6,7,8,9,10,12,13,14

Likurg_2 [28]

4.)
n^2+4n=32
--------------------------
Subtract 32 from each side
n^2+4n-32=32-32
n^2+4n-32=0
--------------------------
Factor left side of equation
(n-4)(n+8)=0
--------------------------
Now set the factors to equal 0
n-4=0
or/and
n+8=0
--------------------------
n=4 and/or n=-8
====================================================================
5.)
t^2-26t=56
Subtract 56 from each side
t^2-26t-56=56-56
t^2-26t-56=0
----------------------------
Factor left side
(t+2)(t-28)=0
--------------------------
Set factors equal to 0
t+2=0
or/and
t-28=0
t = -2 and/or t = 28
===================================================================
As you may have noticed you need to subtract to get 0 on the right side, then you factor the left side and then switch the symbols from the numbers. Negative to Positive and Positive to Negative. I'll keep provided the work for the next 3 or 4 questions
===================================================================
6.)
z^2-14z=72
----------------
Subtract 72 from each side
z^2-14z-72=72-72
z^2-14z-72=0
----------------
Factor left side
(z+4)(z-18)=0
----------------
Set factors equal to 0
z+4=0 or z-18=0
Invert
z = -4 and z = 18
===================================================================
7.)
80+a^2=18a
-------------------------
Simplify
a^2+80=18a
------------------------
Subtract 18a from each side
a^2+80-18a=18a-18a
a^2-18a+80=0
------------------------
Factor left side
(a-8)(a-10)=0
-----------------------
Set factors to equal 0
a-8=0 or a-10=0
Invert
a = 8 and a = 10
===================================================================
8.)
u^2=16u+36
--------------------------
Subtract 16u+36 from both sides.
u^2-(16u+36)=16u+36-(16u+36)
u^2-16u-36=0
--------------------------
Factor left side
(u+2)(u-18)=0
--------------------------
Set factors to 0
u+2=0 or u-18=0
Invert
u = -2 and u = 18
====================================================================
9.)
3h^2+6h=105
--------------------------
Subtract 105 from each side
3h^2+6h-105=105-105
3h^2+6h-105=0
--------------------------
Factor left side
3(h-5)(h+7)=0
--------------------------
Set factors to equal 0
h-5=0 or h+7=0
h = 5 and h = -7
===================================================================
10.)
a^2+14a=-45
---------------------------
Subtract -45 from each side
a^2+14a-(-45)=-45-(-45)
a^2+14a+45=0
--------------------------
Factor left side
(a+5)(a+9)=0
-------------------------
Set factors to equal 0
a+5=0 or a+9=0
Invert
a = -5 and a = -9
===================================================================
12.)
w=5 and w=6
===================================================================
13.)
k=6 and k=-9
===================================================================
14.)
h=5 and h=12

7 0

4 years ago

Use the Statistical Applet: P ‑Value for a Test of One Proportion to answer the question.You have taken a sample of ????=1000 in

umka21 [38]

Answer:

$z=\frac{0.785 -0.7}{\sqrt{\frac{0.7(1-0.7)}{750}}}=5.08$

$p_v =P(z>5.08)=1.88x10^{-7}$

So the p value obtained was a very low value and using the significance level assumed $\alpha=0.05$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 5% of significance the proportion of interest is highr than 0.67 or 67% .

Step-by-step explanation:

1) Data given and notation

n=20 represent the random sample taken

X=15 represent the people who eat breakfast

$\hat p=\frac{15}{20}=0.75$ estimated proportion of people who eat breakfast

$p_o=0.67$ is the value that we want to test

$\alpha=0.05$ represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion is higher than 67%:

Null hypothesis: $p\leq 0.67$

Alternative hypothesis: $p > 0.67$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

3) Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.785 -0.7}{\sqrt{\frac{0.7(1-0.7)}{750}}}=5.08$

4) Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The next step would be calculate the p value for this test.

Since is a right tailed test the p value would be:

$p_v =P(z>5.08)=1.88x10^{-7}$

So the p value obtained was a very low value and using the significance level assumed $\alpha=0.05$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 5% of significance the proportion of interest is highr than 0.67 or 67% .

6 0

3 years ago

What this question?????????

Tanzania [10]

Answer:

A. $\frac{3}{4} = \frac{21}{28}$