1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ratling [72]
3 years ago
11

the force needed to break a board varies inversely with its length. If tom uses 20lb of pressure to break a 1.5 -ft board, how m

any pounds of pressure would he need to use to break a 6 -ft board
Mathematics
1 answer:
jasenka [17]3 years ago
3 0

\qquad \qquad \textit{inverse proportional variation} \\\\ \textit{\underline{y} varies inversely with \underline{x}} ~\hspace{6em} \stackrel{\textit{constant of variation}}{y=\cfrac{\stackrel{\downarrow }{k}}{x}~\hfill } \\\\ \textit{\underline{x} varies inversely with }\underline{z^5} ~\hspace{5.5em} \stackrel{\textit{constant of variation}}{x=\cfrac{\stackrel{\downarrow }{k}}{z^5}~\hfill } \\\\[-0.35em] ~\dotfill

\stackrel{\textit{"f" varies inversely with "L"}}{f=\cfrac{k}{L}}\qquad \textit{we also know that} \begin{cases} f=\stackrel{lbs}{20}\\ L=\stackrel{ft}{1.5} \end{cases} \\\\\\ 20=\cfrac{k}{1.5}\implies 30=k~\hfill \boxed{f=\cfrac{30}{L}} \\\\\\ \textit{when L = 6, what is "f"?}\qquad f=\cfrac{30}{6}\implies f=5

You might be interested in
The general equation for the geometric sequence -1, -2, -4, ... is a n = -1 · 2 n - 1. True or
Feliz [49]
The anwser is probally ture
6 0
3 years ago
Gina walked 0.8 miles before she started jogging at an average pace of 6 miles per hour. The equation d​ = 0.8​ + 6t can be used
Gala2k [10]

Answer:

  • independent: t
  • dependent: d

Step-by-step explanation:

The way the equation is written, d is the dependent variable; t is the independent variable (on which d depends).

7 0
4 years ago
Read 2 more answers
A science student wants to study how fast an ant walks which quantity makes the most sense for his study
klasskru [66]

Inches per second is a convenient unit for ant speed.


Second choice.



4 0
4 years ago
Tain has a great literary tradition that spans centuries. One might assume, then, that Britons read more than citizens of other
tresset_1 [31]

Answer:

Null hypothesis:p_{1} \leq p_{2}  

Alternative hypothesis:p_{1} > p_{2}  

z=3.02  

p_v =P(Z>3.02)=0.00127  

The p value is a very low value and using any significance level for example \alpha=0.05, 0,1,0.15 always p_v so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion of Canadians is not significantly higher than the porportions of readers at Britons.  

Step-by-step explanation:

1) Data given and notation  

X_{1}=0.86*1004 represent the number of Canadians randomly sampled by Gallup that read at least one book in the past year

X_{2}=0.81*1009 represent the number of Britons randomly sampled that read at least one book in the past year

n_{1}=1004 sample of Gallup selected

n_{2}=1009 sample of Britons selected

p_{1}=0.86 represent the proportion of Canadians randomly sampled by Gallup that read at least one book in the past year

p_{2}=0.81 represent the proportion of Britons randomly sampled that read at least one book in the past year

z would represent the statistic (variable of interest)  

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

2) Concepts and formulas to use  

We need to conduct a hypothesis in order to check if the proportion for men with red/green color blindness is a higher than the rate for women  , the system of hypothesis would be:  

Null hypothesis:p_{1} \leq p_{2}  

Alternative hypothesis:p_{1} > p_{2}  

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{0.81+0.86}{2}=0.835

3) Calculate the statistic

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

z=\frac{0.86-0.81}{\sqrt{0.835(1-0.835)(\frac{1}{1004}+\frac{1}{1009})}}=3.02  

4) Statistical decision

For this case we don't have a significance level provided \alpha, but we can calculate the p value for this test.  

Since is a one side test the p value would be:  

p_v =P(Z>3.02)=0.00127  

So the p value is a very low value and using any significance level for example \alpha=0.05, 0,1,0.15 always p_v so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion of Canadians is not significantly higher than the porportions of readers at Britons.  

5 0
4 years ago
Find the mean median mode and range. 5, 8, 11, 13, 14, 15
AlexFokin [52]

Answer:

mean-11

mode-none

range-10

median-12

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
Other questions:
  • A baseball tournament has 7 teams from the Northern League, 5 teams from the Southern League, and 16 coaches attend. Each team h
    13·2 answers
  • What value of x is in the solution set of 8x – 6 &gt; 12 + 2x?<br><br> –1<br> 0<br> 3<br> 5
    13·1 answer
  • (a) Solve by factoring:<br> x2 + 5x - 12 = 8x - 2
    12·2 answers
  • A wooden sign in the shape of a right traingle has perpendicular sides measuring 1.5 m and 1.2 m. How much surface area does the
    7·1 answer
  • PLS HELP BTW DON'T JUST DO IT FOR THE POINTS!!
    12·1 answer
  • When Ricardo was 9 years old, he was 56 inches tall. By age 12, he had increased his
    6·1 answer
  • I GIVE BRAINLISEST
    8·1 answer
  • WHY IS IT SO HARD FOR PPL TO HELP ONE LITTLE GIRL THAT IS ONLY 11 ALL SHE ASK IS PPL NICE PPL TO HELP HER SHE NEEDS HELP ITS NOT
    10·2 answers
  • Is the fraction 45/61 in the simplest form? Explain.​
    9·2 answers
  • If I have 18 employees and I want to give each employee half a cupcake how many cupcakes do I need
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!