Solution :
Group Before After
Mean 693.75 743.75
Sd 155.37 143.92
SEM 54.93 50.88
n 8 8
Null hypothesis : The preparation course not effective.
[tex]$H_0: \mu_d = 0$[/tex]
Alternative hypothesis : The preparation course is effective in improving the exam scores.
[tex]$H_a : \mu_d>0$[/tex] (after - before)
In a 2-digit number, the tens digit is 5 less than the units digit. If you reverse the number, the result is 7 greater than double the original number. Find the original number.
The original number is 38
A 2-digit number can be written as:
N = a*10 + b*1
Where a is the tens digit, and b is the units digit, these two are single-digit numbers.
We know that:
"the tens digit is 5 less than the units digit."
This means that:
a = b - 5
(notice that a must be larger than zero and smaller than 10, from this, we can conclude that b is a number in the range {6, 7, 8, 9})
"If you reverse the number, the result is 7 greater than double the original number"
The reverse number is:
b*10 + a
and this is 7 greater than 2 times the original number, then:
b*10 + a = 7 + 2*(a*10 + b)
Then we found two equations:
a = b - 5
b*10 + a = 7 + 2*(a*10 + b)
Replacing the first equation in the second, we get:
b*10 + (b - 5) = 7 + 2*((b - 5)*10 + b)
Now let's solve that:
b*10 + b - 5 = 7 + 2*(11*b - 50)
11*b - 5 = 7 + 22*b - 100
-5 - 7 + 100 = 22*b - 11*b
88 = 11*b
88/11 = b = 8
Now that we know that b = 8, we can use the equation:
a= b - 5
a = 8 -5 = 3
Then the original number is:
a*10 + b = 3*10 + 8 = 38
The original number is 38
If you want to read more about this, you can see:
https://brainly.com/question/19902993
if a circumference of a circle is 22cm.find it diameter take pie 22/7.
Answer:
➕
Step-by-step explanation:
i know the answer ok it is easy
look at the image below
Answer:
201.1 km²
Step-by-step explanation:
Surface area of the figure,
4πr²
= 4×π×4²
= 64π
= 201.1 km² (rounded to the nearest tenth)
You have $90 in your bank account. Each work you plan to deposit $3 from your allowance and $25 from your paycheck. The equation b: 90+ (25+5)w gives the amount b in your account after w woeks. How rary works from
now will you have $220 in your bank account?
There will be 5220 in the account after works
(Type a whole number
HELPPPP PLZ
Witch statement is true about the value of |6|?
Answer:
The third choice is the correct one.
Step-by-step explanation:
The absolute value of six means that it's the distance from 0 to six, and that distance will be positive regardless of the number being negative or not.
Answer: The third answer is correct
Step-by-step explanation:
Since |6| is the absolute value of positive six, the value of an absolute value of any number is always positive.
Primo car rental agency charges $21 per day plus $0.20 por milo. Ultimo car rental agency charges $24 per day plus $1.00 per milo. Find the daily mileage for which the Ultimo charge is four times the Primo charge.
The mileage is
Answer:
300 miles
Step-by-step explanation:
Let us consider the miles they travelled is 'm'
Mileage for Primo= 21 + (m × 0.20) = 21+0.2m
Mileage for Ultimo= 24+ ( m× 1.00) = 24 + m
Question says The mileage is equal when Ultimo's charge is 4× Primo
Thus,
4 × (21+0.2m) = 24+ m
84 + 0.8m = 24 + m
60 = 0.2m
m = 300
Salaries of entry-level computer engineers have Normal distribution with unknown mean and variance. Three randomly selected computer engineers have following salaries (in $1000s): 70, 80, 90. The average and the standard deviation of the data in the sample are 80 and 10. Using hypothesis testing, determine if this sample provides a sufficient evidence, at a 10% level of significance, that the average salary of all entry-level computer engineers is different from $60,000.
a. Null hypothesis.
b. alternative hypothesis.
c. test statistic.
d. acceptance region.
Answer:
H0 : μ = 60000
H1 : μ ≠ 60000
Test statistic = 3.464
Step-by-step explanation:
Given :
Sample mean salary, xbar = 80000
Sample standard deviation, s = 10000
Population mean salary , μ = 60000
Sample size, n = 3
Hypothesis :
H0 : μ = 60000
H1 : μ ≠ 60000
The test statistic :
T = (xbar - μ) ÷ (s/√(n))
T = (80000 - 60000) ÷ (10000/√(3))
T = 20000 / 5773.5026
T = 3.464
The Decison region :
If Tstatistic >Tcritical
Tcritical at 10%, df = 2 ; two - tailed = 2.9199
Tstatistic > Tcritical ; He
A bicyclist is at point A on a paved road and must ride to point C on another paved road. The two roads meet at
an angle of 38° at point B. The distance from A to B is 18 mi, and the distance from B to C is 12 mi (see
the figure). If the bicyclist can ride 22 mph on the paved roads and 6.8 mph off-road, would it be faster for the bicyclist to ride from A to C on the paved roads or to ride a direct line from A to C off-road? Explain.
Answer:
Step-by-step explanation:
The diagrammatic expression to understand this question very well is attached in the image below.
By applying the law of cosine rule; we have:
a² = b² + c² - 2bc Cos A --- (1)b² = a² + c² - 2ac Cos B --- (2)c² = a² + b² - 2ab Cos C --- (3)From the diagram attached below, we need to determine the side "b" by using equation (2) from above:
b² = a² + c² - 2ac Cos B
From the information given:
a = 12 miles; c = 18 miles; ∠B = 38°
∴
replacing the values into the above equation:
b² = 12² + 18² - 2(12)(18) Cos (38°)
b² = 144 + 324 - 432 × (0.7880)
b² = 468 - 340.416
b² = 127.584
[tex]b = \sqrt{127.584}[/tex]
b = 11.30 miles
However, we are also being told that the speed from A → C = 6.8 mph
Thus, the time required to go from A → C can be determined by using the relation:
[tex]\mathbf{speed = \dfrac{distance}{time}}[/tex]
making time the subject of the formula, we have:
[tex]\mathbf{time= \dfrac{distance}{speed }}[/tex]
[tex]\mathbf{time= \dfrac{11.30}{6.8}}[/tex]
time = 1.66 hours
By using the paved roads, the speed is given as = 22 mph
thus, the total distance covered = |AB| + |BC|
= (18+12) miles
= 30 miles
∴
[tex]\mathbf{time= \dfrac{distance}{speed }}[/tex]
[tex]\mathbf{time= \dfrac{30}{22}}[/tex]
time = 1.36 hours
Therefore, the time used off-road = 1.661 hours while the time used on the paved road is 1.36 hours.
Since we are considering the shortest time possible;
We can conclude that it would be faster for the bicyclist to ride from A to C on the paved roads since it takes a shorter time to reach its destination compared to the time used off-road.
Learn more about Law of cosine here:
https://brainly.com/question/24077856?referrer=searchResults
It would be faster for the bicyclist to ride from A to C on the paved roads since the time to go from A to C on the paved roads is 1.4 h and the time to go from A to C off-road is 1.7 h.
To calculate which way would be faster we need to find the distance from point A to C with the law of cosines:
[tex] \overline{AC}^{2} = \overline{AB}^{2} + \overline{BC}^{2} - 2\overline{AB}\overline{BC}cos(38) [/tex]
Where:
[tex]\overline{AB}[/tex]: is the distance between the point A and B = 18 mi
[tex]\overline{BC}[/tex]: is the distance between the point B and C = 12 mi
[tex] \overline{AC} = \sqrt{(18 mi)^{2} + (12 mi)^{2} - 2*18 mi*12 mi*cos(38)} = 11.3 mi [/tex]
Now, let's find the time for the two following cases.
1. From point A to C on the paved roads (t₁)
[tex] t_{1} = t_{AB} + t_{BC} [/tex]
The time can be calculated with the following equation:
[tex] t = \frac{d}{v} [/tex] (1)
Where:
d: is the distance
v: is the velocity
Then, the total time that it takes the bicyclist to go from point A to C on the paved roads is:
[tex] t_{1} = t_{AB} + t_{BC} = \frac{18 mi}{22 mph} + \frac{12 mi}{22 mph} = 1.4 h = 84 min [/tex]
2. From point A to C off-road (t₂)
With equation (1) we can calculate the time to go from point A to C off-road:
[tex] t_{2} = \frac{\overline{AC}}{v_{2}} = \frac{11.3 mi}{6.8 mph} = 1.7 h = 102 min [/tex]
Therefore, it would be faster for the bicyclist to ride from A to C on the paved roads.
To find more about the law of cosines, go here: https://brainly.com/question/15740431?referrer=searchResults
I hope it helps you!
2. Solve the following system of equations. y = 5 + x 2x + 2y = 30
Sydney has finished all his work on time, but many of his teammates are still struggling to complete their assignments. What should he do? a) Not distract them; they may get farther behind. O b) Listen to them complain about their workloads O c) Help them complete their work d) Share his thoughts on how they could get their work done faster
Answer:
I think the correct option is c
Answer:
I think the correct answer is (d)
Step-by-step explanation:
if he shares his thoughts on how they could get their work done faster like using an app like this, then it would be of great help to them
if the value of a any quadratic function f (x)=ax^2 + BX + C is -8, the function will
Answer:
The parabola will open downward
Step-by-step explanation:
f (x)=ax^2 + BX + C
Since a = -8
The parabola will open downward
When a< 0 the graph opens downwards
a>0 the graph opens upwards
There are 36 tables and 7 booths in the family restaurant. Each table seats 4 people. If the restaurant can seat up to 179 people, what is the capacity of each booth?
4 people
5 people
6 people
7 people
Answer:
5 people.
Step-by-step explanation:
First we need to find how many people 36 tables seats. In order to do this, we need to multiply 36 (tables) by 4 (people sitting) to get 144. Now just subtract 144 from 179 to see how many people are left, here we get 35. Since there are 7 booths, we divide 35 by 7 to get 5. Each booth holds 5 people.
(179-36x4)/7=5
Convert the degree measurement to radians. Express answer as multiple of π: - 60°
A. π/3
B. −π/4
C. −π/5
D. −π/3
Answer:
-pi/3
Step-by-step explanation:
To convert from degree to radians, multiply by pi/180
-60 * pi/180 = -60/180 *pi = -pi/3
Answer:
D. -pi/3
Step-by-step explanation:
degree to radians formula: x=degree, x*pi/180
x=-60
-60*pi/180=-pi/3
8x + 2 = = 7 + 5x + 15
Answer:
2.5
Step-by-step explanation:
8x + 2 = 7 + 5x + 15
Combine like terms:
8x + 2 = 7 + 5x + 15
8x + 2 = 22
-2 -2
-----------------
8x = 20
---- ----
8 8
x = 2.5
Hope this helped.
A 40-foot tree casts a shadow 60 feet long. How long would the shadow of a 6-foot man be at that time?
Answer:
26 ft
Step-by-step explanation:
I'm guessing this is how it's done
60-40= 20
there for at this time any shadow would be 20x it's original height/length
so 6+20=26 ft
lmk if I'm correct
Taking ratios
Let the shadow length=x ft
[tex]\\ \sf\longmapsto 40:60=6:x[/tex]
[tex]\\ \sf\longmapsto \dfrac{40}{60}=\dfrac{6}{x}[/tex]
[tex]\\ \sf\longmapsto \dfrac{4}{6}=\dfrac{6}{x}[/tex]
[tex]\\ \sf\longmapsto 4x=6(6)[/tex]
[tex]\\ \sf\longmapsto 4x=36[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{36}{4}[/tex]
[tex]\\ \sf\longmapsto x=9[/tex]
The graph shows the solution of the following system of equations. y=-5/3x+3 y=1/3x-3 What is the solution? A. (-3,2) B. (3,2) C. (-3,-2) D. (3,-2)
Answer:
(3,-2)
Step-by-step explanation:
-5/3x + 3 = 1/3x - 3
-5/3x = 1/3x - 6
-2x = -6
x = 3
y = -5/3(3) + 3
y = -5 + 3
y = -2
Can someone help me with this?
Answer:
183.3 in^3
Step-by-step explanation:
Find the volume of the rectangular bottom
V = l*w*h
V = 5*5*6 =150 in^3
Find the volume of the triangular pyramid
V = 1/3 Bh where B is the area of the base and h is the height
V = 1/3 ( 5*5) * 4 = 100/3
Add the two volumes together
150 + 100/3
150 +33.3
183.3 in^3
PLS HELP! What is the mistake made below in solving x2 – 12x + 10 = 0 using the completing the square method?
x2 – 12x + 10 = 0
x2 – 12x + (- 6)2 = - 10 + (- 6)2
x2 – 12x + 36 = 26
(x – 6)(x – 6) = 26
x – 6 = √26
x = 6 + √26
Answer:
Step-by-step explanation:
Everything is correct. But you forgot to add
x = 6 - square root of 26. The answer is
x = 6 + square root of 26 or
x = 6 - square root of 26
For the function F defined by F(x) = x2 – 2x + 4, find F(b+3).
Answer:
[tex]\displaystyle F(b + 3) = b^2 + 4b + 7[/tex]
Step-by-step explanation:
We are given the function:
[tex]\displaystlye F(x) = x^2 - 2x + 4[/tex]
And we want to find F(b + 3).
We can substitute:
[tex]\displaystyle F(b + 3) = (b + 3)^2 - 2(b+3) + 4[/tex]
Expand:
[tex]\displaystyle = (b^2 + 6b + 9) + (-2b -6) + 4[/tex]
Rearrange:
[tex]\displaystyle = (b^2) + (6b-2b) + (9 - 6 + 4)[/tex]
Combine like terms. Hence:
[tex]\displaystyle = b^2 +4b + 7[/tex]
In conclusion:
[tex]\displaystyle F(b + 3) = b^2 + 4b + 7[/tex]
what is the answer I need help?
Answer:
8 1/8 units^3
Step-by-step explanation:
This figure is a rectangular prism, and the volume of a rectangular prism is given by the formula:
lwh
But since we have the area of the base snd the height of the figure, there is also one formula that we can use to find the volume:
bh
Which means area of base times the height.
USE THE FORMULA bh:
16 1/4 x 1/2
= 65/4 x 1/2
= 65/8
SIMPLIFIED: 8 1/8
Volume is measured in cubic units
SO YOUR ANSWER IS 8 1/8 units^3
any equations that equal three?
Help!!????
Please!!!????
Answer:
true
mark me brainist if it comes out to be true
Answer:
The answer is TRUE.
Step-by-step explanation:
Draw the line segment with endpoints (-5, 9) and (-1, -7) and find the value of y if x=-4;-2.5;-2;-1.5;0 plz answer asap
Answer:
5, - 1, - 3, - 5, - 11
Step-by-step explanation:
The equation of the line is y=-4x-11. The y values corresponding to x are 5, - 1, - 3, - 5, - 11
Solve the inequality
Answer:
hope this helps buddy, please mark the brainliest.
Step-by-step explanation:
how induction coil work
Answer:
Induction produces an electromagnetic field in a coil to transfer energy to a work piece to be heated. When the electrical current passes along a wire, a magnetic field is produced around that wire
Step-by-step explanation:
a team's stadium has a capacity of 86,047. The fan base is notorious for selling out of tickets every game. If every game sells out this year, how many tickets are sold in their 12 game regular season play?
Answer:
1,032,564 tickets
Step-by-step explanation:
Find how many tickets they sell in total by multiplying the capacity of the stadium by the number of games in the season:
86,047(12)
= 1,032,564
So, if every game sells out, 1,032,564 tickets will be sold.
find x
please help!!
Answer: [tex]9\sqrt{3}[/tex]
==========================================================
Explanation:
For any 30-60-90 triangle, the short leg is always half the hypotenuse.
This makes the short leg to be 18/2 = 9 units long.
We then multiply this by [tex]\sqrt{3}[/tex] to get the length of the long leg.
[tex]\text{long leg} = (\text{short leg})*\sqrt{3}\\\text{long leg} =9\sqrt{3}[/tex]
Or you could use the pythagorean theorem to solve [tex]x^2+9^2 = 18^2[/tex] and you should get [tex]x = \sqrt{243} = 9\sqrt{3}[/tex]
Choose Yes or No to tell if each statement is true.
3
.
072
>
3
.
2
Choose...
728
.
307
>
729
.
07
Choose...
12
.
040
=
12
.
04
Choose...
531
.
135
<
531
.
315
Choose...
Answer:
1. No 2. No 3. Yes 4. Yes
Step-by-step explanation:
Compare the value of each digit from the leftmost digit.
Teddy wants to taste all of the flavors of ice cream at the mall, one by one. Tasting any one flavor will change the way the next flavor taste after it. The flavors are chocolate, vanilla, strawberry, birthday cake, Rocky Road, and butter pecan. In how many ways can he taste the ice cream.
A. 30
B.120
C. 360
D.720
Answer: (d)
Step-by-step explanation:
Given
There are six flavors of ice-cream that is chocolate, vanilla, strawberry, birthday cake, rocky road, and butter pecan
First ice-cream can be tasted in 6 different ways
Second can be in 5 ways
similarly, remaining in 4, 3, 2 and 1 ways
Total no of ways are [tex]6\times5\times 4\times 3\times 2\times 1=720\ \text{ways}[/tex]
Option (d) is correct.
Explain how you would solve the following system of equations using substitution. math step in your explanation, too!! This is the system that you should use: y= 4x -5 y = 3x -3
Answer:
[tex]x=2\\y=3[/tex]
Step-by-step explanation:
Solve by substitution method
[tex]y=4x-5\\y=3x-3[/tex]
First, solve [tex]y=4x-5[/tex] for [tex]y[/tex]:
Substitute [tex]4x-5[/tex] for [tex]y[/tex] in [tex]y=3x-3[/tex]
[tex]y=3x-3[/tex]
[tex]4x-5=3x-3[/tex]
[tex]4x-3x=5-3[/tex]
[tex]x=2[/tex]
Now that we have the value of x
substitute [tex]2[/tex] for [tex]x[/tex] in [tex]y=4x-5[/tex]
[tex]y=4x-5[/tex]
[tex]y=4(2)-5[/tex]
[tex]y=8-5[/tex]
[tex]y=3[/tex]
∴ The value of [tex]x[/tex] is [tex]2[/tex] and the value of [tex]y[/tex] is [tex]3[/tex]
