Answer:
B) 95%
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 37, standard deviation = 2.5
Approximately what percent of the scores fall in the range 32 - 42 ?
32 = 37 - 2*2.5
So 2 standard deviations below the mean
42 = 37 + 2*2.5
So 2 standard deviations above the mean.
This question is the percentage of scores within 2 standard deviations of the mean, so, by the Empirical Rule, it is 95%, option B.
Class A has 12 pupils and class B has 25 pupils.
Both classes sit the same maths test.
The mean score for class A is 80.
The mean score for both classes is 74.
What is the mean score (rounded to 2 DP) in the maths test for class B?
Answer:
71.12
Step-by-step explanation:
80*12= 960
37*74=2738
2738-960=1778
1778/25=71.12
Answer:
71.12
Step-by-step explanation:
80*12= 960
37*74=2738
2738-960=1778
1778/25=71.12
Mark it as brainly please
the perimeter of a square bulletin board is 280 cm how long is one of its side
i follow who answer this;)
Answer:
70cm
Step-by-step explanation:
Perimeter of square= 4×Side
280/4=Side
70=Side
70cm
hope it helps
[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]
Perimeter of square = 4a
280 = 4a
a =
[tex]280 \div 4 = 7 0 [/tex]
Side = 70cmThanks Hope it helpswhat is 4 2/5 - 1 1/4 how would you get the answer
Step 1 [tex]4\frac{2}{5}-1\frac{1}{4}[/tex]
Step 2 [tex]4\frac{2*4}{5*4} - 1 \frac{1*5}{4*5}[/tex]
Step 3 [tex]4 \frac{8}{20} - 1 \frac{4}{20}[/tex]
Step 4a [tex]4 - 1 = 3[/tex]
Step 4b [tex]\frac{8}{20} - \frac{4}{20} = \frac{4:4}{20:4} = \frac{1}{5}[/tex]
Step 5 (final answer) [tex]3\frac{1}{5}[/tex]
In the first week of July, a record 1,020 people went to the local swimming pool. In the second week, 125 fewer people went to the pool than in the first week. In the third week, 145 more people went to the pool than in the second week. In the fourth week, 224 fewer people went to the pool than in the third week. What is the percent decrease in the number of people who went to the pool over these four weeks?
Answer:
The percent decrease in the number of people who went to the pool over these four weeks was of 20%.
Step-by-step explanation:
Percent decrease:
The percent decrease is the decrease multiplied by 100 and divided by the initial value.
Decrease was of:
Second week: - 125
Third week: - 125 + 145
Fourth week: -125 + 145 - 224 = -204
Decrease was of 204.
Percent decrease:
Initially 1,020, then a decrease of 204. So
204*100%/1020 = 20%
The percent decrease in the number of people who went to the pool over these four weeks was of 20%.
Answer: 20%
Step-by-step explanation: jst trust me im gang frl nd i wont get it wrong i promi
What is the measure of angle 1?
Last year, Deshaun had $10,000 to invest. He invested some of it in an account that paid 8% simple interest per year, and
he invested the rest in an account that paid 6% simple interest per year. After one year, he received a total of $660 in
Interest. How much did he invest in each account?
Note that the ALEKS graphing calculator can be used to make computations easier.
Answer:
4
Step-by-step explanation:
y=−8x−3
x+y=7
Is (3,4) a solution of the system?
Answer:
No
Step-by-step explanation:
The given point does not satisfy the first equation.
y = -8(3) -3 = -27
4 ≠ -27 . . . . . the first equation is not satisfied.
Answer: No
Step-by-step explanation:
Plug x and y into y=-8x-3 and calculate:
4 = -24 - 3
4 ≠ 27
Therefore (3,4) is not a solution of the system of equations.
12 ly
Which statement is true regarding the functions on the
graph?
10
8
-6
4
919
Of(6) = g(3)
O f(3) = g(3)
Of(3) = g(6)
Of(6) = g(6)
-6-
2
3 4 5 6 x
4 -3 -2 -12
- fix
-6
-8
-10
-12
Answer: f(3)=g(3)
Step-by-step explanation:
The graphs intersect at x = 3.
The statement "f(6) = g(3)" is true.The correct option is A.
What is a graph?A graph is a structure that amounts to a set of items where some pairs of objects are in some manner "related" in discrete mathematics, more specifically in graph theory.
From the graph, we can see that the value of f(6) is 2, and the value of g(3) is also 2.
The statement "f(3) = g(3)" may or may not be true, as we do not know the values of f(3) and g(3) from the graph.
The statement "f(3) = g(6)" is not true, as the value of f(3) on the graph is -2, and the value of g(6) is 4.
The statement "f(6) = g(6)" is also not true, as the value of f(6) on the graph is 2, and the value of g(6) is 4.
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Chelsea bought a computer on Monday for $1,300. Its value is predicted to decrease by $250 per year. Her brother George also bought a computer on Monday. The function g(x) = 1,100 – 175x predicts how the value of his computer is expected to change after x years.
Whose computer is expected to have a greater value when it is 3 years old, and how much greater will it be?
A) Chelsea’s computer is expected to have a value of $25 greater.
B) George’s computer is expected to have a value of $25 greater.
C) Chelsea’s computer is expected to have a value of $125 greater.
D) George’s computer is expected to have a value of $125 greater.
Answer:
The correct answer is B. George’s computer is expected to have a value of $25 greater.
Step-by-step explanation:
Since Chelsea bought a computer on Monday for $ 1,300, and its value is predicted to decrease by $ 250 per year, while her brother George also bought a computer on Monday, and the function g (x) = 1,100 - 175x predicts how the value of his computer is expected to change after x years, to determine whose computer is expected to have a greater value when it is 3 years old, and how much greater will it be, the following calculation must be performed:
Chelsea:
1,300 - (250 x 3) = X
1,300 - 750 = X
550 = X
George:
1,100 - (175 x 3) = X
1,100 - 525 = X
575 = X
Therefore, George’s computer is expected to have a value of $ 25 greater.
which parent function have a domain of all real numbers? select all that apply.
Answer:
1 2 4 and 6 i believe these are right i checked
From a 60-ft observation tower on the coast, a Coast Guard officer sights a capsized boat. The angle of depression to the
boat is 5º. How far is the boat from the shoreline?
A. 173 ft
B. 523 ft.
C. 686 ft.
D. 60 ft.
C
How far is the boat from the shoreline? C. 686 ft.
PLEASE HELP WILL MARK BRAINLIEST
FIRST PERSON TO ANSWER CORRECTLY GET MARKED BRAINLY
Answer:
[tex]-\frac{14}{25}[/tex]
Step-by-step explanation:
I took the test. (iready)
Simplify [tex]\frac{4}{\sqrt{6} }[/tex]
If the door to the library is at (2, 4), the door to the mall is at (8, 2), and one square unit equals one square mile, the approximate distance between the library and the mall is miles, when measured door to door.
Please help best answer will get brainly
Answer:
https://ihomeworkhelpers.com/mathematics/question512843765
Step-by-step explanation:
MRK ME BRAINLIEST PLZZZZZZZZZZZZZZ
that link is not fake its is a homework helper site if it doesn't works let me know
Answer: 126.66 m²
Step-by-step explanation: The pertinent area formula is a = πr², where r is the radius. here, a = π(6.35 m)² = 40.32π, or approximately 126.66 m²
PLEASE HELP ME 8 NEED THIS FPR A TEST TMRW
When Natalie runs the 400 meter dash, her finishing times are normally distributed with a mean of 71 seconds and a standard deviation of 2.5 seconds. What percentage of races will her finishing time be between 71 and 77 seconds, to the nearest tenth?
Answer:
49.2%
Step-by-step explanation:
It is commonly said that 10 of people are left-handed, but Lilianna suspected that a higher proportion of art students at her university are left-handed. To test this theory, she took a sample of 150 art students and found that p^=14% of the sample was left-handed.
To see how likely a sample like this was to happen by random chance alone, Lilianna performed a simulation. She took a sample of n=150 students from a population where 10% of the students were left-handed, and she recorded what proportion of the sample was left-handed. She repeated this process for a total of 50 samples. Here are the sample proportions from her 50 samples:
She wants to test H0:p=10% vs. Ha:p>10% where p is the proportion of art students at her university who are left-handed.
Based on these simulated results, what is the approximate p-value of the test?
Note: The sample result was p^=14%.
Answer: p-value ≈ 0.08
Step-by-step explanation:
The approximate p-value of the test is 0.0136 as per the data given in question.
What is p-value?The p value is a number calculated from a statistical test that describes the likelihood of finding a specific set of observations if the null hypothesis is true.
To find the approximate p-value of the test, we need to compare the sample proportion p^ to the hypothesized proportion p0 = 10% under the null hypothesis H0:p=10% vs. Ha:p>10%.
Since the sample size n is large (n = 150) and the null hypothesis assumes a normal distribution.
We can use the normal approximation to the binomial distribution. Under the null hypothesis, the test statistic z is given by:
z = (p^ - p0) / sqrt(p0 * (1 - p0) / n)
Plugging in the values, we get:
z = (0.14 - 0.1) / sqrt(0.1 * 0.9 / 150)
z = 2.22
The approximate p-value for this one-tailed test can be found by looking up the area to the right of z = 2.22 under the standard normal distribution.
Using a standard normal distribution table or calculator, we find that the area to the right of z = 2.22 is approximately 0.0136.
Therefore, the approximate p-value of the test is 0.0136. This means that if the true proportion of left-handed art students at the university is 10%, there is approximately a 1.36% chance of getting a sample proportion of 14% or higher by random chance alone.
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President Obama wrote a children's book about extraordinary Americans. One of those
Americans was Albert Einstein. One of Einstein's equations is shown below. Rearrange the
equation to solve for c
E = mc² where Eis energy, m is mass, and c is the speed of light
A) c = (E2 - m)1/2
B) c = E - m2
C) c = (E/m) 1/2
D) c = Em2
Help #1-4 please please just add the symbol addition , subtraction , multiplication or division . I tried 1.subtraction 2&3 division & 4 multiplication but they are wrong so please help
Problem 1
Operation = Subtraction
Estimated answer = 8 dollars
----------------------------
Explanation:
The regular price is estimated at $45, while the sale price is estimated at $37. The two subtract to get 45-37 = 8 dollars, which is about how much you save if you go for the discount price.
The actual amount saved is 45.32-36.50 = 8.82
==========================================================
Problem 2
Operation = Division
Estimated answer = 75 cents
----------------------------
Explanation:
$3.45 rounds to $3
Divide this over 4 to get 3/4 = 0.75, meaning each battery is 75 cents
The actual cost per battery is 3.45/4 = 0.86 dollars = 86 cents.
==========================================================
Problem 3
Operation = Division
Estimated answer = $10
----------------------------
Explanation:
Round $37.45 to the nearest ten to get $40; we could round to 37 but that's an oddball number in my opinion compared to 40. Plus 40 is divisible by 4, leading to 40/4 = 10. Each person chips in about 10 dollars.
The actual amount each person pays is 37.45/4 = 9.36
==========================================================
Problem 4
Operation = Multiplication
Estimated answer = 180 miles
----------------------------
Explanation:
18.75 rounds to 20, which we multiply by 9 to get 180
So the car can travel about 180 miles on 9 gallons. This is an overestimate because 18.75 rounded up to 20
The actual value is 18.75*9 = 168.75
A town is trying to determine if a new recycelin incentive would increase the number of people thatseperate their garbage from recycable iems. to make this determination a simple random sample of 10 streets and the number of people that recycle on these streets is countedonce before and once after the recycling incentive has been intitated. the date shows a mean difference of3.78 and a standard deviation of 1.33.
Required:
Determie if the recycling incentive was effectiive with a 5% significnc level.
Answer:
The recycling incentive was effective at 5% significance level.
Step-by-step explanation:
The null and alternative hypothesis are
H0 u1≤ u2 against the claim Ha: u1> u2
or
H0 ud=0 against the claim Ha: ud > 0
The significance level is ∝=0.05
Data given
d`= 3.78
sd= 1.33
n= 10
The test statistic is
t= d`/ sd/ √n
t= 3.78/1.33/√10
t= 9.3889
The critical region for ∝=0.05 and df.= (n-1)= 9 is t> 1.833
Since the calculated value of t lies in the critical region it is concluded that new recycling incentive would increase the number of people that seperate their garbage from recyclable items.
H0 is rejected and Ha is accepted.
which statement abou y= 7x2 + 23x + 6 is true
Help !!!!!!!!!!!!!!!!!!!!!
Answer:
sorry but I am not able to answer the question
the product of 6 less than a number and 4 more than the
number
Answer:
(x-4)(x+8)
Step-by-step explanation:
Emily is painting every side of the door to her bedroom. The door is a rectangular prism with a length of 35 in, a width of 3 inches and a height of 65 inches.
What is the total amount of space that Emily will cover with paint?
1. 5,150 square inches
2. 6,096 square inches
3. 6,852 square inches
4. 8,002 square inches
Write a sine function that has an amplitude of 5, a midline of 2 and a period of 8pi/5.
Answer:
f(x) = 5*sin( (5/4)*x) + 2
Step-by-step explanation:
A general sine function can be written as:
f(x) = A*sin(w*x) + M
Where:
A is the amplitude
w is the frequency of the function
M is the midline
Here we know that we want to have:
An amplitude of 5. Then, A = 5
A midline of 2, then M = 2
And a period of (8/5)*pi
For now, we can write our function as:
f(x) = 5*sin(w*x) + 2
Now, we know that for a function of period T, is always true that:
f(x) = f(x + T)
here, the period is T = (8/5)*pi
knowing that sin(0) = sin(2*pi)
Then we must have:
sin(0) = sin(w*0) = sin(w*( 0 + (8/5)*pi)) = sin(2*pi)
Then the arguments of the third and fourt parts must be the same, thus:
w*(8/5)*pi = 2*pi
We can solve this for w now:
w*(8/5) = 2
w = 2*(5/8) = (5/4)
Then the function is:
f(x) = 5*sin( (5/4)*x) + 2
Answer: HURRY I need it quick and will give Brainliest Which value of x satisfies the equation StartFraction 12 over StartRoot x plus 2 EndRoot EndFraction plus 8 equals 10?
Answer:
D
Step-by-step explanation:
The length of the base of an isosceles triangle is 8 yards. The height of the triangle is 11 yards. Find the area of the triangle.
Answer:
A=44yd²
Step-by-step explanation:
Select the correct answer. What is the domain of y=cos(x)? PLEASE HELP
y = cos (x) y = cos (x) The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined.
Cos function defines in all range the domain of the y = cos(x) will be all real number.
What is a trigonometric function?The domain input value for the six basic trigonometric operations is the angle of a right triangle, and the result is a range of numbers.
The trigonometric function is only valid for the right angle triangle and it is 6 functions which are given as sin cos tan cosec sec cot.
It will be possible to comprehend the graphs, domains, differentiation, and integration of the four quadrants' trigonometric functions.
The domain of the function y=cos(x) is all real numbers.
Cosine is defined as any angle measure
The range of the angle y will be -1 to 1 which is −1≤y≤1.
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You randomly select a card from a 52-card deck. Find the probability of selecting a 7 or an Ace.
Answer:
15.38%
Step-by-step explanation:
There are 4 7's in a deck of 52 cards.
There are 4 Aces in a deck of 52 cards.
4+4 = 8
8/52, or 15.38%
=================================================
Explanation:
There are four cards labeled "7", and four cards that are aces. We have 4+4 = 8 cards that we want to find. This is out of 52 total.
The probability we're after is 8/52 = (4*2)/(4*13) = 2/13
2/13 = 0.1538 = 15.38% approximately