Answer:
Both students scored in the top 10% of their classes.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
In this question:
Top 10% = Above the 100 - 10 = 90th percentile.
The 90th percentile of scores is X when Z has a pvalue of 0.9, that is, Z = 1.28.
So, the student who had a z-score above 1.28 scored in the 90th percentile of their class.
In student A's class the mean was 78 and the standard deviation of 5. He scored 87.
We have that [tex]\mu = 78, \sigma = 5, X = 87[/tex]
Then
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{87 - 78}{5}[/tex]
[tex]Z = 1.8[/tex]
1.8 > 1.28, so student A scored in the top 10% of his/her class.
Student B's class the mean was 76 with a standard deviation of 4. Scored 87.
We have that [tex]\mu = 76, \sigma = 4, X = 87[/tex]
Then
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{87 - 76}{4}[/tex]
[tex]Z = 2.75[/tex]
2.75 > 1.28, so student B also scored in the top 10% of his/her class.
Both students scored in the top 10% of their classes.
What type of triangle is this if lengths of its sides are 37m, 24m, and 5m *
Answer:
weird triangle
Step-by-step explanation:
Answer:
Scalene triangle
Step-by-step explanation:
Scalene triangle: If the length of all the sides of triangle have different measurements then it is scalene triangle
If Paul saves $3.00 every week for twelve weeks and then buys a CD for $15.00 plus 9% tax, how much money will he have left?
Answer:
18.90
Step-by-step explanation:
3x12=36
36-15=21
21 x 0.9
Answer:
$19.65
Step-by-step explanation:
12*3=36
15*.09=1.35
15+1.35=16.35
36-16.35=$19.65
HELP PLEASE WILL MARK BRAINLEST
Answer:
13x+16
Step-by-step explanation:
3x+7+8x+2x+4+5
13x+7+4+5
13x+16
[(p^q)^r] is equivalent to [p^ (q^r)]
Answer:
True
Step-by-step explanation:
Just write down the answer.
Which triangles are similar to triangle ABC ?
Answer:
both of em
Step-by-step explanation:
Write the equation of the quadratic function shown in the graph.
Answer:
Step-by-step explanation:
y = a(x-h)² + k, where (h,k) is the vertex.
vertex is clearly (0,0), so y = ax².
Plug in (3,3) and solve for a:
3 = a3²
a = ⅓
y = ⅓x²
if $5,250 is invested at 4.5% compounded monthly, what is the amount accumulated at the end of 10 years?
Answer:
In 10 years, you will have $793,789.89
Step-by-step explanation:
Counted with compound interest, i would need to know what was the initial but the answ is $793,789.89
a stone is thrown downward with an intitial velocity of 29.5 m/sec will travel a distance of a meters, where s(t) = 4.9t^2 + 29.4 and t is in seconds. if a stone is thrown downward at 29.4m/sec from a height of 132.3 m, how long will it take the stone to hit the ground?
Answer:
t = 9 s
Step-by-step explanation:
A stone is thrown downward with an intitial velocity of 29.5 m/sec will travel a distance of a meters, where
[tex]s(t) = -4.9t^2 + 29.4+132.3[/tex]
We need to find when the stone will hit the ground. It means when s(t) = 0. So,
[tex]-4.9t^2 + 29.4t+132.3=0\\\\t=-3\ and\ t=9[/tex]
So, the stone will take 9 seconds to hit the ground. Hence, this is the required solution.
You roll a 6-sided die.
What is P(factor of 27)?
A.1/9
B.1/5
C.5/9
D.1/3
Answer:
D
Step-by-step explanation:
because 1 is a factor of every number and also three is a factor of 27
Least common denominator in 1/30 + 1/24
Answer:
The LCD in 1/30 + 1/24 is 90.
What is y if x=6 eqaution=y=4x+5
Calculate the area of the shape below.
Answer:
24 ft²
Step-by-step explanation:
1/2x12x4=24 ft²
help me!!!!!!!!!!!!!
8/7 ( x - 100/220) + 4 ( x + 8/9) = 38
Which color check marks correctly match up the scenarios with their unit rates? *
Green
Red
Blue
Lily has 3 dog toys that are red. One fifth of all her dog toys are red. How many dog toys does Lily have? Complete the explanation. Please I need help!!!!
Answer:
she has 15 dog toys
Step-by-step explanation:
mutlipy 3 by five because the top number is one
what is the radius of a sphere whose surface area is 100cm²?
Answer:
r≈2.82
Step-by-step explanation:
Hope this helps and have a great day!!!
Step-by-step explanation:
that can help you
find the value of k if the roots
of 3x²-5x+k=0, differ by 2
By the fundamental theorem of algebra, we can write the given quadratic in terms of its roots a and b as
3x ² - 5x + k = 3 (x - a) (x - b)
and upon expanding, we have
3x ² - 5x + k = 3x ² - (a + b) x + ab
Two polynomials are equivalent if their coefficients are equal, so
a + b = 5
ab = k
We're given that |a - b| = 2. If we assume a > b (that is, a is the larger root) then |a - b| = a - b = 2, or b = a - 2. Substitute this for b in the first equation above and solve for a :
a + (a - 2) = 5
2a - 2 = 5
2a = 7
a = 7/2
Solve for b :
b = 7/2 - 2
b = 3/2
Solve for k :
k = 7/2 × 3/2 = 21/4
Sales volume last weekend for four samples, each consisting of five car dealerships, were as follows: Data Point 1 2 3 4 5 Sample 1 21 10 19 35 23 Sample 2 34 44 29 15 30 Sample 3 38 22 29 31 15 Sample 4 47 39 20 16 36 What is the mean of the distribution of sample means
Answer:
Mean of sample means = 22.12
Step-by-step explanation:
Data points 1 2 3 4 5 Sample mean
Sample 1 21 10 19 35 23 21.6
Sample 2 34 44 29 15 30 30.4
Sample 3 38 22 29 31 15 27
Sample 4 47 39 20 16 36 31.6
[tex]Mean of means = \frac{Sum of sample means}{No. of samples}[/tex]
[tex]=\frac{21.6 + 30.4 + 27 + 31.6 }{5} \\= 22.12[/tex]
Answer:
22.12
Step-by-step explanation:
Hope this helps
solve for x in the equation
Answer:
third option
Step-by-step explanation:
subtract 125/4 from each side to get:
x² + 11x -1
use quadratic formula to get:
-11 ± √121 - 4(-1)/2
= -11 ± ([tex]\sqrt{125}[/tex]) / 2
* [tex]\sqrt{125}[/tex] = [tex]\sqrt{25}[/tex] · [tex]\sqrt{5}[/tex] = 5[tex]\sqrt{5}[/tex]
= -11 ± (5[tex]\sqrt{5}[/tex]) / 2
How can I find the unknown side lengths when given the area or circumference of a figure?
Answer:
Set up the area/circumference equations using x as the unknown variable. Then, solve for that variable and apply the correct unit.
Step-by-step explanation:
For example,
Find the side length of a square with an area of 49 square centimeters.
Since [tex]area=s^{2}[/tex], i can write [tex]49=s^2\\then take the square root of each side to solve for s.\\s=\sqrt{49} \\s=7 centimeters[/tex]
7m=56. explanation please
Answer:
m=8
Step-by-step explanation:
Divide each term in
7
m
=
56
7
m
=
56
by
7
7
.
7
m
7
=
56
7
7
m
7
=
56
7
Cancel the common factor of
7
7
.
Tap for more steps...
m
=
56
7
m
=
56
7
Divide
56
56
by
7
7
.
m
=
8
m
=
8
Step-by-step explanation:
7m=56
you have to have m by itself so to do that divide 7 on both sides.
7m/7=56/7
the 7 gets cancels on the left side so now you have
m=56/7
you divide
you get m=8
Cindy works on the weekends at the local coffee shop. Last Saturday she worked 7.5 hours and
on Sunday she worked 8 hours. She earns $9 per hour. How much did she earn last weekend?
F:97.00 G:89.50 H:139.50 J:109.00
Answer: H. 139.50
Step-by-step explanation:
Multiply 9 by 8 first and you get 72. Then multiply 9 by 7.5 and you get 67.5 then add 72 and 67.5 and you get 139.5 or 139.50
What will the function f(x) = x² look like translated 3
units right and 8 units down?
Answer:
it will look the same, just shifted.
Step-by-step explanation:
The parabola will be the same shape, size, etc., it will simply be in a different location. Instead of the bottom of the parabola being at (0,0), it will be at (3, -8). translated right 3, down 8.
* Question Completion Status:
QUESTION 3
Find the measure of the unknown angle of the triangle.
18
122
The ratio of red cars to blue cars in a parking lot was 5 : 3. If there were 40 red cars, how many blue cars were there?
Answer:
24 blue cars
Step-by-step explanation:
In this problem, one is given the ratio of red to blue cars in the parking lot. One is given the actual number of red cars, and one is asked to find the number of blue cars. One can set up a proportion; ratio to actual, then solve to find the number of actual blue cars using the method of cross-products. One can set up the proportion using the ratios, but it is easier to express the proportion as the equality of two fractions. Thus, the following equation can be formed, let the parameter (x) represent the actual amount of blue cars;
[tex]\frac{red}{blue}= \frac{5}{3} = \frac{40}{x}[/tex]
Cross products,
[tex]5x = 120[/tex]
Inverse operations,
[tex]x = 24[/tex]
PLS ANSWER QUICK, HELP
Answer:
1014 in
Step-by-step explanation:
(13 x 13) x 6 = 1014 in^3
Answer:
The answer should be A (676)
Step-by-step explanation:
Polygon STUV is reflected over the X axis and then over the Y axis to create WXYZ. Which of the following sides are congruent?
Answer:
ST and WX
Step-by-step explanation:
flipped around st and wx mathched
Answer:
ST and WX
Step-by-step explanation:
for brainliest!!! please help
Answer:
42º
Step-by-step explanation:
90-48=42
Answer:
[tex]42^{o}[/tex]
Step-by-step explanation:
The square angle indicates it is a right angle, which is [tex]90^{o}[/tex]
[tex]90^{o}[/tex] - [tex]48^{o}[/tex] = [tex]42^{o}[/tex]
what is the measure of the missing angle?
The average daily maximum temperature for Shane’s hometown can be modeled by the function f(x)=12.2cos(πx6)+54.9, where f(x) is the temperature in °F and x is the month.
x = 0 corresponds to January.
What is the average daily maximum temperature in March?
Round to the nearest tenth of a degree if needed.
Answer:
The average daily maximum temperature in March is of 61 degrees.
Step-by-step explanation:
The average daily maximum temperature in his hometown in x months after January is given by:
[tex]f(x) = 12.2\cos{(\frac{\pi x}{6})} + 54.9[/tex]
What is the average daily maximum temperature in March?
March is 3 - 1 = 2 months after January, so this is f(2).
[tex]f(2) = 12.2\cos{(\frac{\pi*2}{6})} + 54.9 = 61[/tex]
The average daily maximum temperature in March is of 61 degrees.