1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lyrx [107]
2 years ago
14

Light bulbs are normally distributed with an average lifetime of 1000 hours and a standard deviation of 250 hours. The probabili

ty that a light bulb picked at random will last between 1400 and 1500 hours is about:
Mathematics
1 answer:
Alexus [3.1K]2 years ago
4 0

Answer:

The probability that a light bulb picked at random will last between 1400 and 1500

P(14 00≤X≤1500) = 0.032

Step-by-step explanation:

<u><em>Explanation:-</em></u>

Given that mean of the Population = 1000

Given that the standard deviation of the Population = 250 hours

Let 'X' be the random variable in a normal distribution

Let  X = 1400

Z = \frac{X-mean}{S.D} = \frac{1400-1000}{250} = 1.6

Let X = 1500

Z = \frac{X-mean}{S.D} = \frac{1500-1000}{250} = 2

The probability that a light bulb picked at random will last between 1400 and 1500

P(x₁≤ X ≤x₂) = P(Z₁≤ Z ≤z₂)

                   = A( Z₂ ) -A(Z₁)

P(1400≤X≤1500)  = P(1.6≤ Z ≤2)

                            =  A(2 ) -A(1.6)

                           =  0.4772-0.4452

                          = 0.032

<u><em>Final answer:</em></u>-

The probability that a light bulb picked at random will last between 1400 and 1500

P(14 00≤X≤1500) = 0.032

                   

You might be interested in
Katie has a bag of 15 marbles. There are 3 green, 4 blue, and 5 red marbles. The rest of the marbles are yellow. If Katie random
son4ous [18]

Answer:

P(yellow or red)   =8/15

Step-by-step explanation:

There are 15 marbles, 3 green, 4 blue, and 5 red marbles.

3+4+5 = 12

That means there are 15-12 = 3  3 yellow marbles.

3 green,

4 blue

5 red

3 yellow

To find the probability of yellow or red, we add the number of yellow and red marbles together over the total number of marbles

P(yellow or red) = (yellow +red)/ total

                           = (3+5)/ 15

                             =8/15

8 0
3 years ago
5 2/5+a=71/2 what is the answer to this problem
Gre4nikov [31]
Answer:
30 1/10

Step by step explanation:
71/2-5 2/5= 30 1/10
30 1/10 divided by a (also know as 1) = 30 1/10
3 0
3 years ago
6x + 25; where x = 4
julia-pushkina [17]

Answer:

49

Step-by-step explanation:

6(4)+25

Solve:

6 times 4=24

24+25=49

8 0
3 years ago
Read 2 more answers
Jack is a professional weightlifter. his personal lifting record was 125.8kg. at a weightlifting competition, he broke his own r
Softa [21]

Answer:

126.34kg

Step-by-step explanation:

125.8+0.54=126.34kg

Convert 540 grams to kilograms` 0.54 kilograms, and add to the previous record

5 0
2 years ago
given the line AB with A(1,4) and B(-3,-1) is parallel to line CD with C(8,3) and D(x,-7), solve for the missing value of x.​
umka2103 [35]

Answer:

x = 0

Step-by-step explanation:

We can find the missing value by solving for the other points (graphically or algebraically). We would first find the line of Points A and B in order to find the parallel line that would help us find the coordinate point with the x-value.

1) Graph points A, B, and C.

2) Calculate the slope of points A and B by using the slope formula:

y2 - y1/x2 - x1.  

-1 - 4/-3 - 1....The slope is 5/4.

3) Write 4 = 5/4(x) + b

**We get 4 from the point A (1, 4)

Plug 1 into x and solve for 4 in order to get your y-intercept.

4 = 5/4(1) + b

4 = 5/4 +b

**If 1 = 4/4, then 4 = 16/4.

16/4 = 5/4 + b

11/4 = b

2.75 = b

4) So our y-intercept is 2.75. We now have an equation of  y = 5/4x + 2.75 (graph it along with points A and B to see that it intersect both points.

5) Now we will use that line to find a line parallel to it. We know that if two lines have the same slope then they are parallel, so for the equation of the parallel line, we write: y = 5/4x + b so far.

6) We will find the y-intercept and use that to find the x-value of point D.

First we plug in the x and y values of point C to find the y-intercept

y = 5/4x + b --> 3 = 5/4(8) + b --> 3 = 40/4 + b --> 3 = 10 + b --> -7 = b

7) Now we have the equation of the line that is parallel to line AB: y = 5/4x -7

To find the missing value of x, plug the y-value of point D into the equation and solve for x.

--> -7 = 5/4x -7

--> x = 0

**You can double check this by graphing each point and both equations for the lines.

8 0
2 years ago
Other questions:
  • A fork costs £8.95 . Jay buys seven forks . How much does he spend?​
    8·2 answers
  • If the range of the function f(x) = 4x – 3 is {11.4, 15, 17, 29}, what is its domain?
    15·1 answer
  • Find f if f ''(x) = 12x2 + 6x − 4, f(0) = 5, and f(1) = 4.
    11·1 answer
  • Twice the sum of a number and 7 is more than 6 or at most -3. Which compound inequality can represent this relationship
    12·1 answer
  • Mr. Peter's has 80 sheets of colored paper. Seven of his students need the paper for a project. How many sheets does each studen
    11·1 answer
  • -12divided by 3 help me plz
    8·2 answers
  • The scale drawing can be used to approximate the area of an LCD television. There are 58,000 pixels in the area shown. What is t
    9·1 answer
  • Which decimal is between 0.6 and 0.7
    9·2 answers
  • Find the unit rate<br> 34 carbs for every 1/3 serving
    13·1 answer
  • 3.7% of 35 is what number?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!