Complete Question
It is known that a particular laboratory task takes the average person 2.5 seconds (the variance is not known). A researcher was interested in whether older people are slower (take longer) on this task. The researcher tested 30 randomly selected 80-year-olds. Their mean time was 2.7 seconds, with an estimated population standard deviation of 1.4 seconds. What should the researcher conclude? (Use the .05 significance level and use the five steps of hypothesis testing.)
Answer:
The researchers conclusion is
There is no sufficient evidence to show that older people are slower at the laboratory task
Step-by-step explanation:
From the question we are told that
The mean time is [tex]\mu = 2.5 \ seconds[/tex]
The sample size is n = 30
The sample mean is [tex]\= x = 2.7 \ seconds[/tex]
The standard deviation is [tex]\sigma = 1.4 \ seconds[/tex]
The level of significance is [tex]\alpha = 0.05[/tex]
The null hypothesis is [tex]H_o : \mu = 2.5[/tex]
The alternative hypothesis is [tex]H_a : \mu > 2.5[/tex]
Generally the test statistics is mathematically represented as
[tex]z = \frac{\= x - \mu }{ \frac{\sigma}{\sqrt{n} } }[/tex]
=> [tex]z = \frac{2.7 - 3 }{ \frac{1.4}{\sqrt{30} } }[/tex]
=> [tex]z =0.78[/tex]
From the z table the area under the normal curve to the right corresponding to [tex]z =0.78[/tex] is
[tex]p-value = P(Z > 0.78) = 0.2177[/tex]
From the value obtained we see that the p-value > [tex]\alpha[/tex]
The decision rule is
Fail to reject the null hypothesis
The conclusion is
There is no sufficient evidence to show that the older people are slower at the laboratory task
If a snail travels at a rate of of a mile every of an hour,
what is the unit rate in miles per hour?
Answer:
1mph or 1 mile per hour
Step-by-step explanation:
simple
Brainliest to right answer
Answer:
the answer is A)no solutions
Thomas decides on a destination for his vacation. If he takes the train there, it will take him 1/8 hours to get there. If he takes the plane, it will take him 2/3 hours. How many hours does the plane save?
Answer:
The plane takes [tex]2\frac{11}{24}[/tex] hours shorter.
Step-by-step explanation:
To calculate the number of hours that the plane saves, you must make the difference between the number of hours that must travel by train and the hours that must travel by plane. This is:
[tex]5\frac{1}{8} - 2\frac{2}{3}[/tex]
A mixed fraction is the combination of a whole number and a fraction, as in this case. To subtract mixed numbers, one way to do it is, firstly, to convert both fractions into improper fractions, remembering that the procedure for this consists of multiplying the whole number by the denominator of the fraction, to which the numbered one must be added. of the fraction. This number will be the numerator of the new fraction.
In this case:
[tex]5\frac{1}{8}=\frac{5*8+1}{8} =\frac{41}{8}[/tex]
[tex]2\frac{2}{3}=\frac{2*3+2}{3} =\frac{8}{3}[/tex]
Then:
[tex]5\frac{1}{8} - 2\frac{2}{3}=\frac{41}{8}-\frac{8}{3}[/tex]
Fractions have different denominators, so you need to find a common denominator in order to do the subtraction. A common denominator can be found by multiplying both denominators. Then you rewrite each fraction as an equivalent fraction with a denominator that is the common denominator. Finally you subtract the numerators and simplify the answer if necessary.
In this case:
[tex]5\frac{1}{8} - 2\frac{2}{3}=\frac{41}{8}-\frac{8}{3}= \frac{123}{24} -\frac{64}{24} =\frac{123-64}{24} =\frac{59}{24}[/tex]
Now you write the answer as a mixed number. For that you divide 59 by 24 to obtain 2 with a remainder of 11, being able to express the number as:
[tex]\frac{59}{24} =2\frac{11}{24}[/tex]
So:
[tex]5\frac{1}{8} - 2\frac{2}{3}=2\frac{11}{24}[/tex]
The plane takes [tex]2\frac{11}{24}[/tex] hours shorter.
2, 3, 5, 5, 8, 7, 11, __, __,__, 17,__, __, __
What is the pattern?
Answer:
9, 14, 11, 17, 13, 20, 15
Step-by-step explanation:
so it's kinda hard to explain but starting from 2, for every second number u add three (2,5,8,11,etc) and then starting from 3, for every second number you add two (3,5,7, etc)
that literally makes no sense aha
HELP MEEEEEEEEEEEE WILL GIBE BRAINLISTTTTTTT
Answer:
b
Step-by-step explanation:
Answer:
The answer is C, 2/9
Step-by-step explanation:
Since there 18 marbles in total and 4 blue marbles, that makes the probability 4/18. Although, 4/18 has to be simplified, which is 2/9
For the past 25 days, jonathon has read for n minutes each day. His total number of minutes read is 875. Write an equation to express the number of minutes jonathon read.
Answer:
Required equation is: 25n = 875
Step-by-step explanation:
Let n be the number of minutes Jonathon read per day
Now
He read for 25 days and total 875 minutes
The equation will be:
[tex]25n = 875[/tex]
We can solve this equation to find the number of minutes each day
Using Division property of Equality
[tex]\frac{25n}{25} = \frac{875}{25}\\n = 35[/tex]
Hence,
Required equation is: 25n = 875
2) f(x) = 27x^6+ 1524x^3+125
Answer:
Step-by-step explanation:
Let x^3 = y
f(x) = 27(x^3)^2 + 1524(x^3) + 125
f(x) = 27 y^2 + 1524y + 125
You can now put this into the quadratic formula. When you do, you get
(y + 0.0821)(y+56.3623) = 0
So now you substitute x^3 into this
(x^3 + 0.0821)(x^3 + 56.3623)
x^3 + 0.0821 = 0
x^3 = - 0.0821
cuberoot x^3 = cube root 0.0821
x = - 0.4346
x^3 = - 56.3623
x = - 3.8341
Find the value of x. Then, find the measure of each labelled angle.
x=_
(7x+10)°=_
(15x+16)°=_
Answer:
x = 7deg
Step-by-step explanation:
7x + 10 + 15x + 16 = 180 (angles adjacent to each other in a //polygon are supplementary)
22x = 154
x = 7deg
This is a question on polygons and angles. If you wish to venture further into it/understand this topic better, you may want to follow my Instagram account (learntionary), where I post some of my own notes on certain topics and also some tips that may be useful to you :)
Pi times 2444.57 divided by 344.5=?
Answer:
I think 22.2814177
Step-by-step explanation:
I used 3.14 that's what my teachers tell me to use sorry if it's wrong
Answer: 22.2927232313
Step-by-step explanation: *Pi = 3.14159265359
*3.14159265359 x 2444.57 = 7,679.84315319
*7,679.84315319 ÷ 344.5 = 22.2927232313
Hence, 22.2927232313 = 3.14159265359 x 2444.57 ÷ (344.5)
Suppose a floor is going to be tiled with
square stone tiles that measure ½ foot on
each side. How many tiles are needed for a
rectangular floor that measures 14 ½ feet
long and 8 ½ feet wide?
Answer:
20 tiles
Step-by-step explanation:
Help me please
Question: Write a brief paragraph comparing and contrasting a rectangle and rectangular prism.
Answer:
First of all, rectangles and rectangular prisms have one foremost difference, which is their dimensions. A rectangle has two dimensions whilst a rectangular prism has three. Those dimensions include width, length, and height- but a rectangle has only width and length. Although, in comparison, they're both made from the same quadrilateral: rectangles. A "2D" rectangle has one, while a "3D" rectangle, or rectangular prism, is made of six. The rectangles that make up a rectangular prism can also be referred to as faces.
geometry is experienced that in the early childhood setting through
playing with blocks??
The perimeter of a rectangle is 44 inches, and its area is 112 square inches. Find the length and width of the rectangle.
Answer:
14, 8
Step-by-step explanation:
Using the formulas
A= Length * Width (lw)
P=2(l+w)
l+w)
There are 2 solutions forl
l=P
4+1
4P2﹣16A=44
4+1
4·442﹣16·112=14in
l=P
4﹣1
4P2﹣16A=44
4﹣1
4·442﹣16·112=8in
3/4x16/9????????????
Answer:
It would be 1.33333
Step-by-step explanation:
What is the x-intercept of the graph of - x = 5?
Answer:
x=-5
Step-by-step explanation:
The x-intercept is x=-5
Answer:-5
Step-by-step explanation:If you draw out the graph, it would be a vertical line at the point -5. Since you are asking for the x intercept, it would be -5
8.9 x 7 can u solve it with work shown
Answer:
62.3
Step-by-step explanation:
6
8.9
*7
____
62. 3
I tried to show how to do it but carry the 6 at the top
Answer:
64 (I rounded btw)
Step-by-step explanation:
8.9 × 7 = ??
1. Round 8.9
2. 8.9 can be rounded to 9
3. change equation
4. 9×7= 63
Thus, your answer is 63
(If your supposed to do the math differently tell me and I'll correct it)
(Giving branliest on this 1 !! :D)
Solve five and four tenths times two.
A) ten and four twentieths
B) ten and four tenths
C) ten and eight tenths
Answer:
I am not sure if I am correct but I think it is ten and eight tenths too not a 100% sure
Answer:
its 10 8/10 :) <3
Step-by-step explanation:
What number am I? I am three digits long. My hundreds digit is an odd number. My tens and ones digit are a multiple of 5. All of my digits equal 16.
Answer:
925
Step-by-step explanation:
I think ;)
А
Learning Task 4 : Do the following in your notebook.
A. Find the equation of the line given the graph.
Answer:
Question 3: y =x+2
Step-by-step explanation:
to find the equation use y=mx+c where m is the gradient/slope and c is the y intercept. In example 3, the y intercept is 2 so thats why the equation ends in +2, and the slope which is calculated by rise over run, is 2 over 2, or 1 so x doesnt need a coefficient.
A coin is tossed 5 times find the probability that none are head
Answer:
20%
Step-by-step explanation:
trust me
If it takes one hour for Max to do his homework and it takes Kimberly, his older sister, 1/5 as long to do it. How much longer, in minutes, does it take Max to do his homework than Kimberly?
Answer:
60-12=48min
Step-by-step explanation:
Kimberly takes 12 min, 1/5 of 60 min.
pls help :( plssss plsss pls
Answer:
you can alwayd use desmos for graphing
Mark studied a group of 30 whales. If each whale weird approximately 3.8x10.5 pounds, find the total weight of all 30 whales. Express in Scientific notation.
Answer:
1.197 * 10^3 lbs
Step-by-step explanation:
3.8 * 10.5 = 39.9 lbs each
Now, we multiply 39.9 by 30, which is 1197 lbs in total
In scientific notation, 1197 is 1.197 * 10^3
I hope this helped, please mark Brainliest, thank you !!
Answer:
114 × 10 ^ 5
Step-by-step explanation:
30: Number of whales
380,000: weight of each whale
30 × 38,000 = 11,400,000 total weight
Scentific notation: Expressing large numbers in a smaller way so
114 × 10 exp 5
Which expression is equivalent to -6(-2/3+2X)?
Answer:
4-12x
Step-by-step explanation:
-6(-2/3)= 12/3=4
The fractions 1/4,1/2,3/12 and are shown below
Answer:
the first one
Step-by-step explanation:
The completely factored form of z^5 + 4z^4 - 12z^3
Answer:
−108z 5−64z 3+3z 2−24z−384/6
Step-by-step explanation:i just looked it up.
Given: △ABD cong △CBD. Find each value. (#6)
Answer: m<C= 31
Step-by-step explanation:
To find m<C: Since the triangles are equal, we know that (4x+10) is equal to 90. Then when you put them equal to each other and solve for x you get X=20. Then all you have to do is plug that x value (20) into the equation for the angle of C (x+11). Then you get that C=31 degrees.
Which inequality relates BC and XY?
Answer:
BC>XY
Step-by-step explanation:
BCs angle is less than XYs angle
George claims that he is 3 years less than 3 times as old as his niece Pam will be one year from now. Let p= Pam’s age now. Write an expression to represent George's age. Then simplify the expression. If George is 42 years old now, how old will Pam be next year?
Answer:
G = George's age
G = 3(P+1) - 3
G = 3P + 3 - 3
G = 3P
Step-by-step explanation:
A certain stylist charges $15 for a haircut and $30 for hair coloring. A haircut takes on average 30 minutes, while coloring takes 2 hours. The stylist works up to 8 hours in a day, and she needs to make a minimum of $150 a day to pay for her expenses.
a. Create a system of inequalities that describes the constraints in this situation. Be sure to specify what each variable represents
Answer:
3 hair colorings and 4 hair cuts
Step-by-step explanation:
The time for haircut is 2 hours and for coloring is 6 hours, haircut needs to make a minimum amount of $150.
What is amount?Amount is the multiplication of total number of quantities and total price.
Amount= number of quantity×price.
Given that,
The charges of haircut= $15 and time taken for haircut is 30 minutes,
The charges of coloring= $30 and time taken for coloring is 2 hours.
To make minimum $150 profit in 8 hours
Let in a day he spends x hours for haircut, the 8-x hours will be spent for coloring.
2×x×15+1/2×(8-x)×30≤150
30x-15x+120≤150
15x≤30
x≤2
So, x=2 hours(4 haircut),
then time for coloring = 8-2 = 6 hours (3 hair color)
And amount =4×15+3×30=150
So the time for haircut is 2 hours and for coloring is 6 hours.
To know more about Amount on:
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