Answer:
88
Step-by-step explanation:
Perchlorate is a chemical used in rocket fuel. People who live near a former rocket-testing site are concerned that perchlorate is present in unsafe amounts in their drinking water. Drinking water is considered safe when the average level of perchlorate is 24.5 parts per billion (ppb) or less. A random sample of 28 water sources in this area produces a mean perchlorate measure of 25.3 ppb. Which of the following is an appropriate alternative hypothesis that addresses their concern? Ha : μ < 25.3 H, a, : , μ, < 25.3 A Ha : μ > 25.3 H, a, : , μ, > 25.3 B Ha : μ < 24.5 H, a, : , μ, < 24.5 C Ha : μ > 24.5 H, a , : , μ, > 24.5 D Ha : μ ≠ 24.5
Answer:
[tex]H_a > \mu = 24.5[/tex]
Step-by-step explanation:
Given
[tex]n = 28[/tex] --- sample size
[tex]\bar x = 25.3[/tex] --- Mean
[tex]x = 24.5[/tex] --- Average
Required
Determine the alternate hypothesis
From the question, we understand that it is safe to drink water at 24.5 ppb or less.
This implies that the null hypothesis is:
[tex]H_0 \le \mu = \bar x[/tex]
i.e.
[tex]H_0 \le \mu = 24.5[/tex]
The opposite of [tex]\le[/tex] is [tex]>[/tex]
So, the alternate hypothesis will be:
[tex]H_a > \mu = \bar x[/tex]
[tex]H_a > \mu = 24.5[/tex]
Hence: (c) is correct
4x^2-2x-4=0 solve using quadratic formula
Answer:
Step-by-step explanation:
Although you can start with 4x^2-2x-4=0, it's just slightly easier to reduce the coefficients. 4x^2-2x-4=0 becomes 2x^2 - x - 2 = 0.
The discriminant (part of the quadratic formula) is b^2 - 4ac. Using b = -1. a = 1 and c = -2, we get (-1)^2 - 4(2)(-2), or 17.
-b ± √(b^2 - 4ac)
Then the quadratic formula x = ---------------------------
2a
-(-1) ± √17 1 ± √17
takes on the values x = ----------------- = ---------------
4 4
i have to do a number graph using fractions I dont know how
Answer:
What kind of graph?
Answer this ASAP it’s due tomorrow again
Answer:
76 cm cubed
Step-by-step explanation:
2 x 2 x 4 = 16 cm cubed
3 x 4 x 5 = 60 cm cubed
how do I get from 0 to negative 2
Answer:
Step-by-step explanation:
Are you referring to the number line? Start at “0” and go left to “-2”
(1 point) Carbon dating is often used to determine the age of a fossil. For example, a humanoid skull was found in a cave in South Africa along with the remains of a campfire. Archaeologists believe the age of the skull to be the same age as the campfire. It is determined that only 2% of the original amount of carbon-14 remains in the burnt wood of the campfire. Estimate the age of the skull if the half-life of carbon-14 is about 5600 years.
Answer:
The estimated age of the skull is 39118 years.
Step-by-step explanation:
The amount of the substance after t years is given by:
[tex]A(t) = A(0)(1-r)^t[/tex]
In which A(0) is the initial amount, and r is the decay rate.
The half-life of carbon-14 is about 5600 years.
This means that [tex]A(5600) = 0.5A(0)[/tex]. We use this to find r, or 1 - r, to replace in the equation. So
[tex]A(t) = A(0)(1-r)^t[/tex]
[tex]0.5A(0) = A(0)(1-r)^{5600}[/tex]
[tex](1-r)^{5600} = 0.5[/tex]
[tex]\sqrt[5600]{(1-r)^{5600}} = \sqrt[5600]{0.5}[/tex]
[tex]1 - r = (0.5)^{\frac{1}{5600}}[/tex]
[tex]1 - r = 0.9999[/tex]
So
[tex]A(t) = A(0)(0.9999)^t[/tex]
Only 2% of the original amount of carbon-14 remains in the burnt wood of the campfire.
This is t for which [tex]A(t) = 0.02A(0)[/tex]. So
[tex]A(t) = A(0)(0.9999)^t[/tex]
[tex]0.02A(0) = A(0)(0.9999)^t[/tex]
[tex](0.9999)^t = 0.02[/tex]
[tex]\log{(0.9999)^t} = \log{0.02}[/tex]
[tex]t\log{0.9999} = \log{0.02}[/tex]
[tex]t = \frac{\log{0.02}}{\log{0.9999}}[/tex]
[tex]t = 39118[/tex]
The estimated age of the skull is 39118 years.
route bought a bicycle for 1200 she later sold it for 800 what was her loss
Answer:
-400
Step-by-step explanation:
Answer:
Her loss was 400
Step-by-step explanation:
CP= 1200
SP= 800
L=?
Now,
L= CP - SP
= 1200 - 800
=400
YALL I NEED HELP ASAP !
Answer:
the answer would be 50 rounded to the nearest ten
Step-by-step explanation:
so sorry if this is not correct °3°
okay thanks for reading :P
A line has a gradient of -2
A line that is parallel to this will have a gradient of ...
Given:
A line has a gradient of -2
A line that is parallel to this will have a gradient of ..... .
To find:
The missing value.
Solution:
Gradient of a line is also known as slope of the line.
We know that the slopes of the parallel lines are equal.
A line has a gradient of -2. So, the slopes of all the lines which are parallel to this line have a gradient of -2.
Therefore, the missing value is -2.
5-[6-2-(1-8) -3 +6]+5 =
Answer:
-4
Step-by-step explanation:
5 - [6 - 2 - (1 - 8) - 3 + 6] + 5 =
Simplify.
5 - [6 - 2 + 7 - 3 + 6] + 5 =
Subtract
5 - [4 + 7 - 3 + 6] + 5 =
Add
5 - (11 - 3 + 6) + 5
Subtract
5 - (8 + 6) + 5
Add
5 - 14 + 5
Simplify by adding and subtracting.
-4
good luck, i hope this helps :)
Answer:
[tex]sln \\ 5 - (6 - 2 - (1 - 8) - 3 + 6) + 5 \\ 5 - (4 - ( - 7) + 3) +5\\ 5 - (4 + 7 + 3)+5 \\ 5 - (14) +5\\ 5 - 14 \\ - 9[/tex]+5
=-4
I hope this help
Paige's hair was originally 7 inches long. she asked her hair dresser to cut1/2 of it off. how many inches did she cut off
Answer:
3.5 inches
Step-by-step explanation:
half of 7 is 3.5
which alphabet is missing C C D F I _
Answer:
Answer is M.
Step-by-step explanation:
I hope it's helpful!
What is the angle Between two parallel lines? Hmm?ಠ_ಠ
Answer:
the angle between parallel lines is undefined, or it can be either 0 or 180 degrees, or any multiple of 180 degrees.
Answer:
the angle between two parallel lines are supplementary (180 degrees) if intersected by a transversal..
Please I need this question ASAP
Mona has 160 yards of fencing to enclose a rectangular area. Find the dimensions of the rectangle that maximize the enclosed area
see topper. com
Step-by-step explanation:
uyhhghjggg
A cylinder has a diameter of 19 inches. It has a volume of about 3,400.62
cubic inches. Find the height.
I don't need a explanation I just need to know what are the two answers thankyou!
Answer:
(4.7) ⁴
(4.7)-⁴
Step-by-step explanation:
Mark brainliest please
I need help if the awnser is right I will mark you
Answer:
C. 344 square centimeters
Jack can text 210 characters in 21 minutes. Write an expression for m minutes.
a. 10m
b. 210m
c. 21m
d. 12m
Select all expressions that are equivalent to 16x-12-24x+4.
pls help ASAP!
The line perpendicular to y= (-3/2)x -4 and goes through (1,4)
Answer (assuming it is allowed to be in point-slope format):
[tex]y-4 = \frac{2}{3}(x-1)[/tex]
Step-by-step explanation:
1) First, determine the slope. We know it has to be perpendicular to the given equation, [tex]y = -\frac{3}{2} x-4[/tex]. That equation is already in slope-intercept form, or y = mx + b format, in which m represents the slope. Since [tex]-\frac{3}{2}[/tex] is in place of the m in the equation, that must be the slope of the given line.
Slopes that are perpendicular are opposite reciprocals of each other (they have different signs, and the denominators and numerators switch places). Thus, the slope of the new line must be [tex]\frac{2}{3}[/tex].
2) Now, use the point-slope formula, [tex]y-y_1 = m (x-x_1)[/tex] to write the new equation with the given information. Substitute [tex]m[/tex], [tex]x_1[/tex], and [tex]y_1[/tex] for real values.
The [tex]m[/tex] represents the slope, so substitute [tex]\frac{2}{3}[/tex] in its place. The [tex]x_1[/tex] and [tex]y_1[/tex] represent the x and y values of a point the line intersects. Since the point crosses (1,4), substitute 1 for [tex]x_1[/tex] and 4 for [tex]y_1[/tex]. This gives the following equation and answer:
[tex]y-4 = \frac{2}{3}(x-1)[/tex]
Write and equivalent expression for the following expression: ab
Answer:
ab = a(b)
Step-by-step explanation:
cuz u can just add parentheses
Solve the exponential equation: 4x – 2 = 1∕4
Question 9 options:
A)
x = 1
B)
x = –1
C)
x = –2
D)
x = 2
4
Step-by-step explanation:
I do not know but maybe 1/4
3c=6 and after you have to do subtraction to check
Answer:
c=2
Step-by-step explanation:
Given function:
3c=6divide 6 by 3 to find c.
6÷3=2subtract to check:
6-3=3since there are 2 threes, c=2.Therefore, c=2.
Select the correct answer from each drop-down menu.
Gilbert is training for a bike race. As part of his training, he does practice rides on portions of
and his second practice ride covers 9 miles of the course. Between these practice rides, he in
These functions model the time it took Gilbert to do each practice ride, where x is his speed
Practice Ride 1
Practice Ride 2
9
+ 2
The denominator of the function that models practice ride 2 represents the
To find a function that models the total amount of time Gilbert spent doing practice rides on
Reset
N
Answer:
I need help on this as well
Answer:
1.biking speed for the second practice ride
2.add
Step-by-step explanation:
This is right for plato bc i got it right:)
Ricardos bill at a restaurant is $57.32. He wants to leave an 18% tip. what will the new total be including tip.
Answer:
$67.64
Step-by-step explanation:
[tex]57.32*1.18=67.6376\\[/tex]
Rounding it off to the nearest cent, we get $67.64.
Jason delivered pizzas to a house in Southaven. The pizzas cost the customer $18.25. They tipped Jason $3.65. At what percent did they tip Jason? (HOW DID YOU GET YOUR ANSWER PLEASE SHOW ME YOUR WORK!!)
A. 16.6%
B. 50%
C. 20%
D. 5.6FT
E. $29.40
F. $30.40
G. 6.3FT
H. 25%
Answer:
$3.65/$18.25
Step-by-step explanation:
$3.65/$18.25
=0.2=2%
This is the correct answer
question:
2r - 13 = -5
Answer:
r = 4
Step-by-step explanation:
2r = 13 + -5
2r = 8
r = 4
Hope that helps!
What is the equation of a line that passes through (0, 6) and (6, 0)?
a.y = -x
b.y = x - 6
c.y = x + 6
d.y = -x + 6
PLZ HELP IN A TEST
12/7 ÷ 12/7 = ??????????
Answer:
1
Step-by-step explanation:
Anything divided by itself is always 1.
Answer:
the answer is 1
Step-by-step explanation:
