Answer:
from step 3 to step 4
Step-by-step explanation:
because 2x-7=3 is equal to 2x=3+7=10
not 2x=-4 so 3 is false so even four is incorrect
You measure the period of a mass oscillating on a vertical spring ten times as follows:
Period (s): 1.06, 1.31, 1.28, 0.99, 1.48, 1.37, 0.98, 1.31, 1.59, 1.55
Required:
What are the mean and (sample) standard deviation?
a. Mean: 1.228, Standard Deviation: 0.2135
b. Mean: 1.325, Standard Deviation: 0.1674
c. Mean: 1.292. Standard Deviation: 0.2211
d. Mean: 1.228, Standard Deviation: 0.2098
e. Mean: 1.292, Standard Deviation: 0.2135
Answer:
Step-by-step explanation:
Mean is the ratio of sum of the dataset to the sample size. Mathematically:
[tex]\overline x = \frac{\sum Xi}{N}[/tex]
Xi are the individual periods
N is the sample size
[tex]\sum Xi = 1.06+1.31+1.28+0.99+1.48+1.37+0.98+1.31+1.59+1.55\\\sum Xi = 12.92[/tex]
N = 10
Substitute
[tex]\overline x = \frac{12.92}{10}\\\overline x = 1.292[/tex]
hence the mean of the samples is 1.292
For the standard deviation:
[tex]\sigma = \sqrt{\frac{\sum (x-\overline x)^2}{N} } \\[/tex]
[tex]\sum (x-\overline x)^2 = (1.06-1.292)^2+ (1.31-1.292)^2+ (1.28-1.292)^2+ (10.99-1.292)^2+ (1.48-1.292)^2+ (1.37-1.292)^2+ (0.98-1.292)^2+ (1.31-1.292)^2+ (1.59-1.292)^2+ (1.55-1.292)^2\\\sum (x-\overline x)^2 = 0.43996[/tex]
Substitute into the formula:
[tex]\sigma = \sqrt{\frac{0.43996}{10} }} \\\sigma = \sqrt{{0.043996}}} \\\sigma = 0.2098[/tex]
Hence the standard deviation is 0.2098
SOMEONE PLEASE HELP ILL GIVE BRAINLIEST
Answer:
A.
Step-by-step explanation:
Based on the survey results from 300 selected students in the Burbank School District (BSD), the 98% confidence interval used to estimate the population proportion of all BSD students who have access to a working computer at home was computed to be 48% to 60%. The following 2 subquestions require a numeric input, no work is necessary. [2 points] What number of students (out of the 300 sampled) have access to a working computer at home
Answer:
follows are the solution to this question:
Step-by-step explanation:
Please find the correct question in the attached file:
The formula for calculating the Confidence interval of proportion:
[tex]\to CI=\hat{p} \pm Z_{\frac{\alpha}{2}} \sqrt{\frac{\hat{p}(1-\hat{p})}{n}}\\\\\to \hat{p}=\frac{\text{lower limit +upper limit}}{2}\\[/tex]
[tex]=\frac{0.48+0.60}{2}\\\\=\frac{1.08}{2}\\\\=0.54[/tex]
The number of learners with access to working at home on a computer:
[tex]= 0.54 \times 300 \\\\=162[/tex]
Lower limit =0.48
upper limit = 0.60
[tex]\to margin \ error = \frac{\text{upper limit - lower limit}}{2}\\[/tex]
[tex]=\frac{0.60-0.48}{2}\\\\=\frac{0.12}{2}\\\\= 0.06[/tex]
If a roof has a pitch of 5 to 11, how high will the roof rise over a 33-foot run?
a.
3
C.
2
72 feet
1 feet
b. 15 feet
d.
20 feet
The answer is b. 15ft
Which equation shows y=3x−15 in standard form?
A. 15x−5y=1
B. 15x+5y=−1
C. 5x−15y=1
D. 5x−15y=−1
Answer:
c 5x -15y =1
Step-by-step explanation:
5x-15y=1
-5x -15y= 1 -5x change the signs on both sides of the equation
15y = -1 +5x divide both sides by 15
y = -1/15 + 1/3 x Reorder the terms
y = 3x-15
:)
All options are wrong here.
Given equation is [tex]y=3x-15[/tex].
the equation given here is in form of [tex]y=mx+c[/tex] . The general equation of any straight line where m is the gradient of the line (how steep the line is) and c is the y -intercept (the point in which the line crosses the y -axis) .
We have to write [tex]y=3x-15 \\[/tex] in standard form.
The standard form for linear equations in two variables is Ax+By=C.
Now we convert [tex]y=3x-15[/tex] in standard form.
Here [tex]y=3x-15\\[/tex]
[tex]y-3x=-15\\\\-y+3x=15[/tex]
[tex]3x-y=15[/tex]
But no options match with the above standard form of equation.
Hence all options are wrong here.
For more details on standard form for linear equations follow the link:
https://brainly.com/question/7380540
Michael exercises more than 35 minutes per day.
Use t to represent Michael's amount of exercise (in minutes per day).
Answer:
t>35
Step-by-step explanation:
Since Michael exercises more than 35 days, t is greater than 35. To express that in an inequality, the answer is t>35. Hope this helped!
what are factors of 7
Answer:
1 and 7
Step-by-step explanation:
anyone in flvs? we should find each other in live lessons lol
Answer:
nope
Step-by-step explanation:
Which equation shows the variable terms isolated on one side and the constant terms isolated on the other side for the
equation 3x-5=-2x+ 10?
A. X=5. B.—5=x. C.—15=—5x. D.—5x=15
Answer:
A; (X=5)
Step-by-step explanation:
Move the constants and variable terms to one side:
3x-5= -2x+10
-5+10= -2x+ 3x
Combine like terms:
5=x or x=5
Answer:
The answer is C
Step-by-step explanation:
If you take the equation and simplify it.
3x-5=-2x+10
You would minus 3x from both sides, leaving the equation like
-5=-5x+10
Then you would minus 10 from both sides, leaving the equation like
-15=-5x
If you wanted to go further you could divide both sides by -1 and get rid of the negatives. Leaving the equation like
15=5x
Then to put it into the simpleist form you would divide both sides by 5, leaving the equation like
3=x
I hope this helps.
What is the first step when solving the equation 3(3x-5x)+2=-8
Answer:
Collect the like terms
Step-by-step explanation:
(3x-5x)
3x (-2x) + 2 = -8
If b^2 = 25 then b= Answer it please
Answer:
b = 5
mark me as brainliest plz!! :DD
You have 8 donuts and you want to give 1/4 of them to a friend. How many donuts would your friend get?
Answer: pretty sure the friend would get 2 donuts
Step-by-step explanation:
If it takes 930 kg of food to feed a pair
of elephants for 3 days, how much food
would you need to feed them for a week?
Answer:
2170
Step-by-step explanation:
930 divided be 3= 310
310 multiplied by 7=2170
Ellie bakes 12 muffins everyday since Monday. Jacob said that on Friday, she would be able to bake 72 muffins in total. Is Jacob right? Yes or no, explain. :)
7th grade math help me plzzzz
Answer:
a. -14
b. -13
c. -5
d. -3
e. -12
f. 0
Step-by-step explanation:
hope it helps
Answer:
A is -14.
B is -13
C is -5
D is -3
E is -12
F is 0
Step-by-step explanation:
A, B, E both numbers are negative so you just add them together and add a negative sign.
C would read 4-9
D 10-7 and add a - to the answer
F is 6-6
8 tomatoes for $2 unit rate
I don't have much so please 17
30 point question! WILL AWARD BRAINLIEST!
A ball is thrown across a playing field from a height of h = 5 ft above the ground at an angle of 45° to the horizontal at the speed of 20 ft/s. It can be deduced from physical principles that the path of the ball is modeled by the function
y = − (32/(20^2))x2 + x + 5
Find the horizontal distance the ball has traveled when it hits the ground. (Round your answer to one decimal place.)
Answer:
Answers are down below ;)
Step-by-step explanation:
y = − (32/(20^2))x2 + x + 5
Plug into the calculator: -32/20^2 = -.08x^2
Find the maximum height attained by the ball:
Rewrite the equation:
y= -.08x^2 + x +5
This parabola is a negative meaning that it will be maximum
to find the maximum we use the formula -b/2a
-(1)/ 2 (-.08) = -1/ -.16= 6.25
we plug 6.25 back into the equation y= -.08(6.25)^2+ (6.25) +5 = 8.125
The maximum height attained by the ball: 8.125 feet
Find the horizontal distance the ball has traveled when it hits the ground.
This can be found with the quadratic equation, x = [-b ± √(b2-4ac)]/2a
a= -.08 , -b= -1, c= 5 (When you are plugging in the numbers, make sure to break them down).
-(-1)± √(-1)^2-4(-.08)(5)] 2(-.08) -->
[-1 ± √(1 + 1.28)]/-.16 = [-1 ± √(2.6)]/-.16 = [-1 ± 1.61]/-.16 =
The horizontal distance of the ball is x = 16.31 feet
Say thank you by commenting down below :)
Your teacher invented another game: You will pick one card from a deck of cards. If
you pick a heart, you will win $25.00. Otherwise, you will lose $5.00.
From the standpoint of the player, what is the expected value of this game?
Enter expected value
What does the expected value tell us about the game?
O The game is good to play, you will make money on average.
O The game is NOT good to play, you will tend to lose money.
O It doesn't matter if you play, you will generally break even.
Answer:
C
Step-by-step explanation:
Dale has three dollars more than twice the amount of money that Leo has.
Which statement makes this comparison using the correct variable expression?
A. If Leo has d dollars then Dale has 2(3) + D dollars.
B. If Leo has d dollars then Dale has 2d + 3 dollars.
C. If Leo has d dollars then Dale has d +2+3 dollars.
D. If Leo has d dollars then Dale has d/2 + 3 dollars.
Please help y'all I don't get this can you guys explain to?
Answer:
is leo has d dollars then dale has 2d + 3 dollars
Step-by-step explanation:
dale has twice the amount and three extra dollars.
so 2 x d is 2d
2d + 3
estimate the answer for 1 2/3 x 5 1/10 (type a whole number
Answer:
Exact Form:
17/2
Decimal Form:
8.5
Mixed Number Form:
8 1/2
A man walks along a straight path at a speed of 4 ft/s. A searchlight is located on the ground 20 ft from the path and is kept focused on the man. At what rate is the searchlight rotating when the man is 15 ft from the point on the path closest to the searchlight
Answer:
0.128rad/sec
Step-by-step explanation:
Let x represent the between the man and the point on the path
θ = the angle
dx/dt = 4 ft/s
dθ/dt = rate is the searchlight rotating when the man is 15 ft from the point on the path closest to the searchlight
tan θ = x/20 ft
Cross Multiply
20tan θ = x
dx/dt = 20sec² θ dθ/dt
dθ/dt = 1/20 × cos² θ dx/dt
dθ/dt= 1/20 × cos² θ × 4
dθ/dt = 1/5 × cos² θ
Note : cos θ = 4/5
dθ/dt = 1/5 × (4/5)²
dθ/dt = 16/125
dθ/dt = 0.128rad/sec
QUICK
solve this equation
a^n+b^n=
Help me with this question quick PLZz
Answer:7 to 3
Step-by-step explanation:
Answer:
3:10
Step-by-step explanation:
3 Parrots
Total Number of Birds: 3+7=10
janesa has 24 coins in her pocket worth exactly $1.00. she tells her younger brother jackson that he can have the coins if he correctly guesses how many of each coin she has. she gives him the hint that there are only nickels and pennies. complete the equation that represents the total value of the nickels and p pennies 5( blank ) + p = 100
Answer:
Number of Nickels = 19
Number of pennies = 5
Step-by-step explanation:
The type of coins that Janessa has = nickels and pennies.
Janessa has a total number of 24 coins
The sum of the nickels and pennies = $1.00
Let us represent the number of nickels as x
The number of pennies as y
Hence, our system of equations is :
x + y = 24..... Equation 1
x = 24 - y
A nickel is worth 5 cents.
1 nickel = $0.05
A penny is worth 1 cent.
1 penny = $0.01
Therefore,
$0.05× x + $0.01 × y= $1.00
0.05x + 0.01y = 1.00........Equation 2
Substitute 24 - y for x in Equation 1
0.05(24 - y) + 0.01y = 1
1.2 - 0.05y + 0.01y = 1
1.2 - 1 = 0.05y - 0.01y
0.2 = 0.04y
y = 0.2/0.04
y = 5
We have 5 pennies
x = 24 - y
x = 24 - 5
x = 19
We have 19 nickels
The distance between Point P and Point Q was 3600 m. Beng Leong started jogging
at 08 35 from Point P and reached Point Q at 08 50. At the same time, Sam started
jogging from Point P at a speed of 200 m/min. Who jogged at a faster speed?
How much faster was his speed?
Answer:
Ben ran at a speed of 240m/min and Sam ran at a speed of 200m/min So Ben is faster by a rate of 40/min
Step-by-step explanation:
Ben's miles per minutes
[tex] \frac{3600}{15} = 240[/tex]
Sam's miles per minute
Given
Which ordered pair, if included in this relation, would cause it to no
longer be a function?
Answer:
(-6,3)
Step-by-step explanation:
your job requires that you work at least 40 hours a week you have already worked 15 and there are 4 more days left in the week how many hours do you have to work each day to get at least 40 hours: inequality and solution
Answer:
6.25 hours
Step-by-step explanation:
this is rather simple really,
first, you have to work 40 hours a week
you have already worked 15 so now you can subtract that
40-15= 25hrs
if you have 4 more days of the week you divide the remaining hours by the days left
25/4= 6.25hrs
that would be the bare minimum of hours for you to work a 40 hour week.
5 divided 5/6 helpabacon hair please
Answer:
what? expalint the question
Step-by-step explanation:
A circle is inscribed in a square. If the perimeter of the square is 40, what is the area of the circle? Use 3.14 for pi.
Answer:
78.5
Step-by-step explanation:
We have the perimeter of the square, which is 40, and 40/4=10. In this picture, we see that the circle's diameter is the same as the length of one side of the square. Therefore, the diameter of the circle is 10. The are formula for circles is [tex]\pi r^{2}[/tex], where [tex]r[/tex] is the radius. The radius of the circle is just the diameter divided by 2, and 10/2=5. Now, [tex]5^2[/tex] is 25, and [tex]3.14\cdot25=78.5[/tex].
Translate the sentence into an equation.
Seven times the sum of a number and 2 is 6.
Use the variable y for the unknown number.
Answer:
7(y+2)=6
Step-by-step explanation:
its right