Answer:
31.92% probability that 18 randomly selected bulbs would have an average life of no more than 260 days
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
In this question, we have that:
[tex]\mu = 270, \sigma = 90, n = 18, s = \frac{90}{\sqrt{18}} = 21.2[/tex]
What is the probability that 18 randomly selected bulbs would have an average life of no more than 260 days?
This is the pvalue of Z when [tex]X = 260[/tex]. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{260 - 270}{21.2}[/tex]
[tex]Z = -0.47[/tex]
[tex]Z = -0.47[/tex] has a pvalue of 0.3192.
31.92% probability that 18 randomly selected bulbs would have an average life of no more than 260 days
A taxi company charges $9 for pick-up plus $0.35 for each mile. Select the expressions that represent the cost in dollars for a taxi pick up and m miles. Select all that apply.
A. 9+0.35m
B. 9m+ 0.35
C. 0.35m+9
D. The product of 9 and m plus 0.35
Please answer quick
If 45% of a number, n, is 225, what is 74% of n?
Answer: 375
hope this helps :D
Step-by-step explanation:
225/45=5
5=1%
5 times 74 equals 375
△GFH is similar to △CDE. Identify the corresponding congruent angles.
Answer:
∠G ≅ ∠C
∠F ≅ ∠D
∠H ≅ ∠E
Step-by-step explanation:
if you have 4 B's and 2 A's then what is your GPA
Answer:
3.33
Step-by-step explanation:
(4a^15b)^3 there is a photo to go with it
Answer:
I believe it's option 3
explanation: you times inside by 3
Answer:
option 1.
Step-by-step explanation:
(4a⁵b)³ = 4³ * (a⁵)³ * b³
[tex]= 64 *a^{5*3} * b^{3}\\\\= 64a^{15}b^{3}[/tex]
PLEASE HELP, QUICK
10 POINTS
Answer:
x = 1
y = 10
(1,10)
hope that helps :)
Write the equation of the line in point-slope form that goes through the points (0, 1) and (2, 7)
Answer:
point - slope form
y - 1 = 3 (x-0)
Step-by-step explanation:
step(i):-
Given points are (0,1) and (2,7)
The slope of the line
[tex]m = \frac{y_{2}-y_{1} }{x_{2} -x_{1} }[/tex]
[tex]m = \frac{y_{2}-y_{1} }{x_{2} -x_{1} } = \frac{7-1}{2-0} = \frac{6}{2} = 3[/tex]
m =3
Step(ii):-
point -slope form
y - y₁ = m(x-x₁)
Equation of the straight line passing through the point (0,1) and having slope 'm' = 3
y - 1 = 3 (x-0)
y -1 = 3x
3x - y +1=0
Equation of the straight line passing through the point (0,1) and having slope 'm' = 3 is 3x -y +1=0
Solve for X
X/3-X/4=X/6
[tex] \huge \blue{solution}[/tex]
[tex] \bold \red{ \frac{x}{3} - \frac{x}{4} = \frac{x}{6} }[/tex]
[tex] \bold \red{ \frac{4x + 3( - x)}{3 {2}^{2} } = \frac{x}{6} }[/tex]
[tex] \bold \red{ \frac{4x - 3x}{3 {2}^{2} } = \frac{x}{6} }[/tex]
[tex] \bold \red{\frac{x}{3 {2}^{2} } = \frac{x}{6} }[/tex]
[tex] \bold \red{ - x = 0}[/tex]
[tex] \bold \red{x = 0}[/tex]
w+6=2(w-6) what is the answer?
Answer:
w = 18
Step-by-step explanation:
w+6 = 2(w-6)
w+6 = 2w-12
2w-w = 6+12
w = 18
hope it helps
Answer:
[tex] \huge \boxed {w = 18}[/tex]
Step-by-step explanation:
Distribute 2 in the bracket.
[tex]w + 6 = 2w - 12[/tex]
A constant and variable cannot add up or subtract each others. Therefore, move the same term to the same side.
[tex]12 + 6 = 2w - w \\ 18 = w[/tex]
Answer Check
Substitute w = 18 in the equation.
[tex]18 + 6 = 2(18) - 12 \\ 24 = 36 - 12 \\ 24 = 24[/tex]
Therefore w = 18 is the correct answer.
PLEASE HELP MEEE ASAP THIS IS DUR SOON
Answer:
I am pretty sure it is A because it is -5 and then +2
Step-by-step explanation:
I hope this is right
I hope this helps you...
Answer:
option A
Step-by-step explanation:
the arrow goes from 0-5 then another from 5-3
12. What is the value of the y-coordinate of the solution to the system of equations x - 2y = 1 and x + 4y = 7?
(1) 1
(2) -1
(3) 3
(4) 4
Answer:
(3,1)
value x is 3
value y is 1
What is the slope of the line below?
Answer:
37
Step-by-step explanation:
I saw it there in the picture
Answer:
m=2
Step-by-step explanation:
use the slope formula m=y2-y1/x2-x1
Points: (0,4) (-2,0)
m=0-4/ -2-0
m=-4/-2
m=2
I really need help on this please and thank you in advance
Answer:
Step-by-step explanation:
first, your answer will be negative,
x^12*(2y)^3=x^12(8y^3)
denominator= -x^2*y^12
after we divide them=- 8 x^10/y^9
choice E
10.
(02.01 LC)
Simplify 8 over negative 4 ÷ negative 3 over 9 . (5 points)
6
-6
12
-12
Answer:
The answer is 6
Step-by-step explanation:
First nothing us negative, so multiply 8/4 times 9/3,which is 72/12=6, 6×12 is 72.The reason why it is 9/3 instead of 3/9 is because you are dividing so KCF, keep change flip.
Answer:
Positive 6
Step-by-step explanation:
What you do is:
8 x 9 = 72
-4 x (-3) = 12
72 / 12 = 6
Hope this helps!
- 28allemm
What is 150% of 625? Solve using an equation.
Answer:
937.5
Step-by-step explanation:
150%=150/100
Equation:150/100 x 625
937.5
2. in a class of 50 students, the number of females is 2 more than 5 times the number of males. How many males and females are there in the class?
Answer:
There are 8 males in the class and 42 females.
Step-by-step explanation:
This question can be solved using a system of equations.
I am going to say that:
x is the number of females.
y is the number of males.
Class of 50 students
This means that [tex]x + y = 50[/tex]
The number of females is 2 more than 5 times the number of males.
This means that [tex]x = 5y + 2[/tex]
So, finding y, the number of males:
[tex]x + y = 50[/tex]
[tex]5y + 2 + y = 50[/tex]
[tex]6y = 48[/tex]
[tex]y = \frac{48}{6}[/tex]
[tex]y = 8[/tex]
Females:
[tex]x = 5y + 2 = 5*8 + 2 = 42[/tex]
There are 8 males in the class and 42 females.
Please help me answer this
Answer:
Brand A
Step-by-step explanation: Brand A because y=50x+100 and that equals 150x. For brand B y=25x+200 and that equals 225x. So Brand A is lower.
You and your family went out to eat at The Cheesecake Factory. The bill is $120, you want to leave an 18% tip and have to pay a 6% tax. What is the total you have to pay for the everything?
Find the tip:
$120 * 18% =
$120 * 0.18 =
$21.60
Find the tax:
$120 * 6% =
$120 * 0.06 =
$7.20
Find the answer:
$120 + $21.60 + $7.20 =
$148.80
2) You traveled 210 miles in 3.5 hours.
How many miles will you travel per hour?
Answer:
= 56.7 miles per hour
Step-by-step explanation:
Step-by-step explanation:
To find the average speed for the entire journey, we need to find the entire distance and the total time
Entire distance = 210 miles + 130 miles = 340 miles
Total time = 3.5 hours and 2.5 hours = 6 hours
Average speed = distance/ time = 340 miles/ 6 hours
= 56.66666666666 miles per hour
Rounding to the nearest tenth
= 56.7 miles per hour
Answer:
60 miles
Step-by-step explanation:
Step 1:210=3.5
x =1
Step 2: cross multiply3.5×x= 210×1
3.5x=210
Step 3: divide both sides by the coefficient of x which is 3.53.5x/3.5=210/3.5
x=60
Answer= 60 miles
Bob drove 65 miles per hour for 3 hours, how far did he drive
Answer:
195 miles
Step-by-step explanation:
Answer:
195 miles.
Step-by-step explanation:
In 1 hour Bob drove = 65 miles
In 3 hours, Bob drove = 3 * 65 = 195 miles.
Hope it will help :)
Solve: –3x – 7 < 11
Α) α
X > -2
B
2 <
2
С
x < -2
D
2 > -6
Answer:
Step-by-step explanation:
Here you go mate
Step 1
-3x-7<11 Equation/Question
Step 2
-3x-7<11 Simplify
-3x-7<11
Step 3
-3x-7<11 Add
-3x<18
Step 4
-3x<18 Divide by 3
answer
x>-6
Hope this helps
What is the slope of the line through (-4, 2) and (3,-3)?
Choose 1 answer:
A: -5/7
B: 7/5
C: 5/7
D: -7/5
Answer:
A
Step-by-step explanation:
To the nearest unit, what is the perimeter of this pentagon?
5
3
2
1
2
4
-6 -5 -4 -3 -2 -1 0
-1
2
-3
-4
-5
sh
27 units
0 29 units
0 30 units
0 34 units
Answer: 27 units
Step-by-step explanation: I just did the test and Got it right
A school supply company is giving away free whiteboards to promote their stain-free markers. The company can spend up to $42,840 on the whiteboards. If each whiteboard costs the company $8, how many whiteboards will they be able to give away?
Answer:the whiteboards free
Step-by-step explanation:
PLS HELP ASAP WILL GIVE BRAINLIEST
Answer:
it would be the second answer
Step-by-step explanation:
Easy math Can someone please help me
Answer:
4.2 cm
Step-by-step explanation:
Given
Area of parallelogram (A) = 4.2 cm²
base (b) = 1.75 cm
Height (h) = ?
We know
A = b * h
4.2 = 1.75 * h
h = 4.2 / 1.75
H = 2.4 cm
Hope it will help
.
If the cells continue to double every 5 minutes, how
long will it take to fill 3 additional bottles of the same
Size?
I minutes
Done
Intro
Answer:
10 min.
Step-by-step explanation:
Taylor will order one t-shirt for each person who attends her family's reunion. The cost is
$8 per t-shirt plus a one-time printing fee of $40.00. This can be represented by the
equation c = 8n + 40, where c represents the total cost of the shirts and n represents
the number of shirts ordered. If the family can spend no more than $600.00 on t-shirts,
what is the maximum number they can order?
B) 75
C) 70
A) 80
D) 15
Answer:
C) 70
Step-by-step explanation:
Since they can only spend a maximum of $600, we can fill that in for c. Now, we can solve the equation for n.
600 = 8n + 40
~Subtract 40 to both sides
560 = 8n
~Divide 8 to both sides
70 = n
Best of Luck!
1 foot = 12 inches therefore 5 feet = what
Answer:
60 inches
Step-by-step explanation:
1 foot = 12 inches
5 feet = ?
5*12 = 60
[tex]1\cdot \text{foot} = 12\cdot \text{inches} \implies 5 \cdot\text{foot} =5\cdot 12 \cdot\text{inches} \implies 5 \cdot\text{foot} =60 \cdot\text{inches}[/tex]
5 divided by 4 in fractions one with a whole and one without
Plsss help I don’t want an f
Answer:
5/4 or 1 1/4
Step-by-step explanation: