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OverLord2011 [107]
3 years ago
13

You are interested in determining which of two brands of light bulbs, brand A and brand B, lasts longer under differing conditio

ns of use. Fifty Bovano lamps are fitted with brand A light bulbs and 50 Bulbrite lamps are fitted with brand B light bulbs. Each light bulb is left on for 20,000 hours straight. Light bulb life is then measured for each bulb, and the average light bulb life for the two brands is compared. What is wrong with this experimental design?
Nothing is wrong with this design.
The type of lamp is a confounding variable.
Not enough light bulbs of each type are used in the study.
The experiment should have been conducted on more than two brands of lamps.
Mathematics
2 answers:
bulgar [2K]3 years ago
7 0

Answer:

The type of lamp is a confounding variable.

Step-by-step explanation:

to test the average life of the bulbs the same lamps should be used

Fofino [41]3 years ago
5 0

Answer:

The answer would be A. 1 1/5

Hope this helps!!!

Step-by-step explanation:

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A box contains 100 colored chips; some are pink and some are blue. Milton chooses a chip at random, records the color, and place
Lena [83]

The approximate number of pink chips is 40. Here's why: what you need to do is set up the problem as shown below. 12 goes above 30 because you have to know what the total number of chips chosen is in order to relate it to 100 chips. From there, all you have to do is cross-multiply and divide (or my middle school teacher used to call it fish.... I'll explain why). First you are going to draw a line from the 100 to the 12 and multiply them. then you are going to curve the line that you will draw from the 12 to the 30 and divide the product of 12 and 100 by 30. Then you will draw a line from the 30 to the X meaning that the quotient that you find from the product of 120 and 100 divided by 30 equals X.  Hope that helps.

12      x    

30   100  

4 0
3 years ago
Read 2 more answers
I need the answer and the work (it’s geometry)
Kisachek [45]

Answer:

D

Step-by-step explanation:

The starting point is B and the ray extends towards A.

So the asnwer is D.

6 0
3 years ago
不是我要的<br>营养分,<br>一、加;<br>的<br>第一<br>年11<br>在公司<br>16<br>115<br>更多<br>11<br>(<br>-<br>日) 上海​
ludmilkaskok [199]

Answer:

您能再解釋一下嗎,謝謝

Step-by-step explanation:

3 0
3 years ago
The manager wants to advertise that anybody who isn't served within a certain number of minutes gets a free hamburger. But she d
aksik [14]

Answer:

The number of minutes advertisement should use is found.

x ≅ 12 mins

Step-by-step explanation:

(MISSING PART OF THE QUESTION: AVERAGE WAITING TIME = 2.5 MINUTES)

<h3 /><h3>Step 1</h3>

For such problems, we can use probability density function, in which probability is found out by taking integral of a function across an interval.

Probability Density Function is given by:

f(t)=\left \{ {{0 ,\-t

Consider the second function:

f(t)=\frac{e^{-t/\mu}}{\mu}\\

Where Average waiting time = μ = 2.5

The function f(t) becomes

f(t)=0.4e^{-0.4t}

<h3>Step 2</h3>

The manager wants to give free hamburgers to only 1% of her costumers, which means that probability of a costumer getting a free hamburger is 0.01

The probability that a costumer has to wait for more than x minutes is:

\int\limits^\infty_x {f(t)} \, dt= \int\limits^\infty_x {}0.4e^{-0.4t}dt

which is equal to 0.01

<h3>Step 3</h3>

Solve the equation for x

\int\limits^{\infty}_x {0.4e^{-0.4t}} \, dt =0.01\\\\\frac{0.4e^{-0.4t}}{-0.4}=0.01\\\\-e^{-0.4t} |^\infty_x =0.01\\\\e^{-0.4x}=0.01

Take natural log on both sides

ln (e^{-0.4x})=ln(0.01)\\-0.4x=ln(0.01)\\-0.4x=-4.61\\x= 11.53

<h3>Results</h3>

The costumer has to wait x = 11.53 mins ≅ 12 mins to get a free hamburger

3 0
3 years ago
Are snow days a thing of the past or do they still have a place in today's world? Answer whether or not you believe the Mayor an
Aleksandr [31]

Answer:

I feel it is unfair to kids of today to require work in bad weather. Especially in harsh and even dangerous weather conditions. For me what if power goes out should I be required to do work?

5 0
2 years ago
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