Mark and eight of his friends went out to
eat. They decided to split the bill evenly.
Each person paid $9. What was the total
bill?
A bin of 5 transistors is known to contain 2 that are defective. The transistors are tested one at a time until both defective transistors have been identified. Denote N1 the number of tests until the first defective is identified and N2 the number of tests until the second defective is identified. (a) Find the joint probability mass function of N1 and N2.
Answer:
sorry I donot know the answer never mind ok
When electricity (the flow of electrons) is passed through a solution, it causes an oxidation-reduction (redox) reaction to occur. If the solution contains a metal cation such as Ag+, the flow of electrons will reduce the silver ion, causing solid silver to plate onto the electrode. The amount of metal plated depends on the number of electrons passed. The total charge of a mole of electrons is 96, 485 coulombs (C) and 1 ampere = 1 coulomb/second (C/s).
What mass of Cu(s) is electroplated by running 28.5 A of current through a Cu2+ (aq) solution for 4.00 h? Express your answer to three significant figures and include the appropriate units.
How many minutes will it take to electroplate 37.1 g of gold by running 5.00 A of current through a solution of Au+(aq)? Express your answer to three significant figures and include the appropriate units.
Answer:
a. 135 g
b. 60.6 min
Step-by-step explanation:
a. What mass of Cu(s) is electroplated by running 28.5 A of current through a Cu2+ (aq) solution for 4.00 h? Express your answer to three significant figures and include the appropriate units.
The chemical equation for the reaction is given below
Cu²⁺(aq) + 2e⁻ → Cu(s)
We find the number of moles of Cu that are deposited from
nF = It where n = number of moles of electrons, F = Faraday's constant = 96485 C/mol, I = current = 28.5 A and t = time = 4.00 h = 4.00 × 60 min/h × 60 s/min = 14,400 s
So, n = It/F = 28.5 A × 14,400 s/96485 C/mol = 410,400 C/96485 C/mol = 4.254 mol
Since 2 moles of electrons deposits 1 mol of Cu, then 4.254 mol of electrons deposits 4.254 mol × 1 mol of Cu/2 mol = 2.127 mol of Cu
Now, number of moles of Cu = n' = m/M where m = mass of copper and M = molar mass of Cu = 63.546 g/mol
So, m = n'M
= 2.127 mol × 63.546 g/mol
= 135.15 g
≅ 135 g to 3 significant figures
b. How many minutes will it take to electroplate 37.1 g of gold by running 5.00 A of current through a solution of Au+(aq)?
The chemical equation for the reaction is given below
Au⁺(aq) + e⁻ → Au(s)
We need to find the number of moles of Au in 37.1 g
So, number of moles of Au = n = m/M where m = mass of gold = 37.1 g and M = molar mass of Au = 196.97 g/mol
So, n = m/M = 37.1 g/196.97 g/mol = 0.188 mol
Since 1 mol of Au is deposited by 1 moles of electrons, then 0.188 mol of Au deposits 0.188 mol of Au × 1 mol of electrons/1 mol of Au = 0.188 mol of electrons
We find the time it takes to deposit 0.188 mol of electrons that are deposited from
nF = It where n = number of moles of electrons, F = Faraday's constant = 96485 C/mol, I = current = 5.00 A and t = time
So, t = nF/It
= 0.188 mol × 96485 C/mol ÷ 5.00 A
= 18173.30 C/5.00 A
= 3634.66 s
= 3634.66 s × 1min/60 s
= 60.58 min
≅ 60.6 min to 3 significant figures
construct a rectangle (a and b of known length, d diagonal)
point a and point b are placed on a number line point a is located at -20 and point b is 5 less then point a Wich statement about point b is true
Answer:
Step-by-step explanation:
D beause less then 5 that means it gose down the grid
In 2001, gas cost $1.85 per gallon. In 2008, the price was
220% higher than in 2001.
What was the cost of gas per gallon in 2008?
A right triangle has a hypotenuse of 15 cm. What is the length for the missing leg if one of the two legs of the triangle is 5?
Answer:
The other leg is 12 cm long.
Step-by-step explanation:
c
2
=
a
2
+
b
2
,
where:
c
is the hypotenuse, and
a
and
b
are the other two sides (legs).
Let
a
=
9 cm
Rearrange the equation to isolate
b
2
. Plug in the values for
a
and
c
, and solve.
b
2
=
c
2
−
a
2
b
2
=
(
15 cm
)
2
−
(
9 cm
)
2
Simplify.
b
2
=
225 cm
2
−
81
cm
2
b
2
=
144 cm
2
Take the square root of both sides.
b
=
√
144 cm
2
Simplify.
b
=
12 cm
Answer:
14.14 cm
Step-by-step explanation:
using the Pythagorean theorem:
?² = 15² - 5² = 225 - 25 = 200
? = √200 = 14.14 cm
It has been reported that 8.7% of U.S. households do not own a vehicle, with 33.1% owning 1 vehicle, 38.1% owning 2 vehicles, and 20.1% owning 3 or more vehicles. The data for a random sample of 100 households in a resort community are summarized in the frequency distribution below. At the 0.05 level of significance, can we reject the possibility that the vehicle-ownership distribution in this community differs from that of the nation as a whole?
Number of Vehicles Owned Number of Households 0 20 1 35 2 23 3 or more 22 =100
Answer:
Here, the test statistics ( 20.951 ) is greater than the critical value ( 7.815 )
Therefore, we reject H₀ at 0.05 level of significance.
Hence, there is significant evidence to support the claim that In this community, vehicle ownership distribution is NOT like that of all U.S household
Step-by-step explanation:
Given the data in the question;
Number of vehicle owned Number of households
0 20
1 35
2 23
3 or more 22
Total ( n ) 100
so
Null hypothesis H₀ : In this community, vehicle ownership distribution is like that of all U.S household
Alternative hypothesis Hₐ : In this community, vehicle ownership distribution is NOT like that of all U.S household
Also given that, ∝ = 0.05
Now, we compute the test statistics;
x² = ∑[ ( O[tex]_i[/tex] - E[tex]_i[/tex] ) / E[tex]_i[/tex] ]
where E[tex]_i[/tex] is expected frequency and O[tex]_i[/tex] is observed frequency.
so we make our table for chi square test statistics
No. of O[tex]_i[/tex] P E[tex]_i[/tex] (O[tex]_i[/tex] - E[tex]_i[/tex])² (O[tex]_i[/tex] - E[tex]_i[/tex])²/E[tex]_i[/tex]
Vehicle (n×P)
owned
0 20 0.087 8.7 127.69 14.677
1 35 0.331 33.1 3.61 0.109
2 23 0.381 38.1 228.01 5.985
3 or more 22 0.201 20.1 3.61 0.180
Total 100 100 20.951
hence, x² = 20.951
Now, degree of freedom df = k - 1 = 4 - 1 = 3
From Chi-Square critical value table; ( right tailed test ) for ∝ = 0.05
[tex]x_{0.05, 3[/tex] = 7.815
Decision Rule
Reject H₀ if x² is greater than xₐ².
Here, the test statistics ( 20.951 ) is greater than the critical value ( 7.815 )
Therefore, we reject H₀ at 0.05 level of significance.
Hence, there is significant evidence to support the claim that In this community, vehicle ownership distribution is NOT like that of all U.S household
Help me with my homework, please
Answer:
150°
Step-by-step explanation:
We know each angle in a equilateral triangle is 60° and that of a rectangle is 90° . So ,
[tex]\implies \angle ABC = \angle DBC + \angle ABD \\\\\implies \angle ABC = 90^o + 60^o \\\\\implies \boxed{\boxed{ \angle ABC = 150^o }}[/tex]
I am voting in a state election. There are seven candidates for governor, four candidates for lieutenant governor, three candidates for the state house of representatives, and four candidates for the senate. In how many different ways can I fill out a ballot if I vote once for each office?
Answer:
4
Step-by-step explanation:
CHOOSE 1 GOVERNOR
CHOOSE 1 LIEUTENANT GOVERNOR
CHOOSE 1 STATE HOUSE REP'.
CHOOSE 1 SENATOR
=4 DIFFERENTNT WAYS.
Simplify (6x2 - 4x + 7) - (8x2 - 2x + 5) =
Answer:
−2x 2−2+2
Step-by-step explanation:
What is the range of y = 7x^2 + 14x – 9?
Answer:
-1,-16
Step-by-step explanation:
y=ax^2+box+c
Which function represents a quantity growing exponentially?
A y = 2(0.5)
В y = 0.5(2)
C y = 2(0.5)2X
D y = 6)
Answer: c
Step-by-step explanation:
Which statement about the ordered pairs (–2, 9), (0, 9) and (3, 9) is not true?
Answer:
The slope of these coordinates is 0.
It is a horizontal line.
Step-by-step explanation:
write the first five terms of the sequence an=3n^2
Answer:
2,1,0 is the sequence of its terms
HELPPPPP WILLLLL AMRK BRAINLIESTTTTTT
Is 3/4 closer to 0 or 1?
Answer:
It is closer to 1
Step-by-step explanation:
3/4 is 1/4 away from 1, whereas 0 is 3/4 away from 3/4. So, 1 is closer.
The fraction 3/4 is closer to 1.
We have,
To determine whether the fraction 3/4 is closer to 0 or 1, we can compare the distances between 3/4 and 0, and between 3/4 and 1.
The distance between 3/4 and 0 is 3/4.
The absolute value of the difference is |3/4 - 0| = 3/4.
The distance between 3/4 and 1 is 1 - 3/4 = 1/4.
Since the distance between 3/4 and 1/4 (which is 1/4) is smaller than the distance between 3/4 and 0 (which is 3/4), we can conclude that 3/4 is closer to 1 than to 0.
In other words, if we were to plot the fractions 0, 3/4, and 1 on a number line, the distance between 3/4 and 1 would be smaller than the distance between 3/4 and 0.
Therefore,
The fraction 3/4 is closer to 1.
Learn more about fractions here:
https://brainly.com/question/24370499
#SPJ2
Mia's birthday party will cost $12 if she invites 4 guests. What is the maximum number of guests there can be if Mia can afford to spend a total of $15 on her birthday party?
Describe how to transform the graph of g(x)=ln(x) in the graph of f(x) = ln(-x)-9
Answer:
the answer is d because it's reflects
8. A box is filled with candies in different colors. We have 40 white candies, 24 green ones, 12
red ones, 24 yellow ones and 20 blue ones. If we have selected one candy from the box
without peeking into it, find the probability of getting a green or red candy.
Answer:
[tex]P(Green\ or\ Red) = 0.30[/tex]
Step-by-step explanation:
Given
[tex]White = 40[/tex]
[tex]Green = 24[/tex]
[tex]Red = 12[/tex]
[tex]Yellow = 24[/tex]
[tex]Blue = 20[/tex]
Required
[tex]P(Green\ or\ Red)[/tex]
The total numbe of candy is:
[tex]Total = 40 + 24 + 12 + 24 + 20[/tex]
[tex]Total = 120[/tex]
This probability is calculated as:
[tex]P(Green\ or\ Red) = P(Green) + P(Red)[/tex]
For each, we have:
[tex]P(Green\ or\ Red) = \frac{Green}{Total} + \frac{Red}{Total}[/tex]
Take LCM
[tex]P(Green\ or\ Red) = \frac{Green+Red}{Total}[/tex]
[tex]P(Green\ or\ Red) = \frac{24+12}{120}[/tex]
[tex]P(Green\ or\ Red) = \frac{36}{120}[/tex]
[tex]P(Green\ or\ Red) = 0.30[/tex]
Find the mean, median and mode of the following data sets.
1. 79, 84, 92, 81, 86, 77, 95, 80, 88, 84
2. 8, 9, 9, 9, 9, 10, 11, 15
3. 16, 23, 18, 30, 32, 34, 8, 19, 21
Answer:
1.
mean= 84.6
median=84
mode=84
2.
mean=10.14
median=9
mode=9
3.
mean=22.3
median=21
mode=phi
Step-by-step explanation:
mean: the sum of of the quantities by their number
median: the median value after rearranging the values
mode: the value that occurs most frequently
in the second question
mean = (8+9+9+9+9+10+11+15)/8
median(even number) =(9+9)/2=9
mode=9
Answer:
for data set 1
1.mean-84.6
2.median-(84+84)/2 = 84
3.mode-84
for data set 2
1.mean-9.25
2.median-(9+9)/2 = 9
3.mode-9
for data set 3
1.mean-22.3
2.median-21
3.mode-no mode with this data set
hope this helped!!
I don’t know the answer
Answer:
(a+b) (a-b) =a^2 - b^2
In this question a=2, b=square root of 5
So 2*2=4 square root of 5 times square root of 5 is 5
4-5=-1
Answer:
I believe the answer is -1.
Step-by-step explanation:
So I distributed,
2 x 2 = 4
[tex]-\sqrt{5}[/tex] x 2 = [tex]-2\sqrt{5}[/tex]
[tex]\sqrt{5}[/tex] x 2 = [tex]2\sqrt{5}[/tex]
[tex]\sqrt{5}[/tex] x [tex]-\sqrt{5}[/tex] = -5
4 [tex]-2\sqrt{5}[/tex] + [tex]2\sqrt{5}[/tex] - 5 = ?
the radicals cancel out and 4 -5 = -1
SOMEONE HELP ME WITH THISS
Answer:
/_ 12 is the angle of depression from the firefighter to the second story window.
Step-by-step explanation:
Hope it helps!
#CarryOnLearning
Answer:
2nd option is the correct answer
Step-by-step explanation:
[tex] \angle 12[/tex] is the angle of depression from the second story window to the firefighter.
What type of correlation is shown in the graph?
Answer:
no correlation
Step-by-step explanation:
it shows no trend or a line thing
also i think your pic is upside down haha
PLEASE HELP PLEASE
A girls' choir is choosing a uniform for their concert. They can pick red, green or
purple sweaters, and they can pick tan, white or black skirts. The shoes they need
come in gold and black. Assuming all combinations are acceptable, how many
different combinations can the choir pick?
Answer:
18
Step-by-step explanation:
=============================================================
Explanation:
There are 3 colors to pick for the sweaters (red, green, purple).There are 3 colors for the skirts (tan, white, black)There are 2 colors for the shoes (gold, black)Multiply out those values mentioned to get the final answer: 3*3*2 = 9*2 = 18.
There are 18 different outfit combos.
---------------
Further explanation (optional section):
Let's say we only worried about the sweaters and shoes, and for now there's only one color for the skirt. We have 3 colors for the sweaters and 2 for the shoes. Imagine a table with 3 rows and 2 columns. Each row is a different color for the sweater and each column is a different color for the shoe. There are 3*2 = 6 cells inside the table. Each cell is a different outfit.
For instance, we could have R = red sweater and G = gold shoe. Then that means RG = red sweater + gold shoe outfit. So we'd have RG as one of the cells of this 6 cell table.
Now imagine that we laid out a table that is 6 by 3. The 6 is from the 6 outfits calculated earlier, and the 3 is now accounting for the colors of the skirts. We'd then have 6*3 = 18 combos total. Again, each cell inside the table represents a different outfit combo.
What is the difference of the rational expressions below?
6x _ 5
X-2 X
A. 6x2 -5x - 10
x(x - 2)
B. 6x-5
2X-2
c. 6x^2 -5x +10
x(x-2)
D. 6x-5
-2
I'm
C.) 6x^2-5x+10/x(x-2)
pls help
its was on khan academy
i will mark u brainiest!!!
Answer:
[tex]14 units[/tex]
Step-by-step explanation:
[tex]Solution:-[/tex]
[tex]A(5,1)B(7,1)[/tex]
[tex]\sqrt{(x_{1}-x_{2} ) ^{2}(y_{2} -y_{1}x^{2} }[/tex]
[tex]AB=\sqrt{(7-5)^{2} +(1-1)^{2} }[/tex]
[tex]= \sqrt{2^{2} } =2[/tex]
[tex]BC=\sqrt{7-7^{2}+(6-1)^{2} }[/tex]
[tex]=\sqrt{5^{2} } =5[/tex]
[tex]perimeter=2(AB)+2(BC)[/tex]
[tex]= 2(2)+2(5)\\[/tex]
[tex]= 4+10= 14[/tex]
[tex]-----------[/tex]
hope it helps...
have a great day!!
What linear expression would you add to -4y+2 to have a sum of y
Answer:
4
Step-by-step explanation:
Help with number 10! Step by step please!
9514 1404 393
Answer:
x = -9 (as you know)
Step-by-step explanation:
[tex]\log_6\dfrac{1}{6}=\dfrac{x}{9}\\\\\log_6{(6^{-1})}=\dfrac{x}{9}\\\\-1=\dfrac{x}{9}\\\\x=(-1)(9)=\boxed{-9}[/tex]
_____
I find it helpful to remember that a logarithm is an exponent.
[tex]\log_a(a^b)=b[/tex]
What is the area of parallelogram ABCD?13 square units14 square units15 square units16 square units
Answer:
13
Step-by-step explanation:
the equation for parrlelograms is base times hieght. the base is about 3 and the hieght is 4 and 1/3 (ish) so 3*4.3 would give the answer of 13 square units. I hope this helps?