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
user100 [1]
3 years ago
5

A concerned mother wants to ensure that her children are drinking pure water. Specifically, she wants to compare the water quali

ty that comes from her kitchen sink to that which runs through her stand-alone water-filtration system.
She purchases a device that measures the contamination of the water on a scale of 0–100, where 0 indicates no contaminants and 100 means the water is fully contaminated and unsuitable for human consumption.
She selects 30 samples of water from her kitchen sink. She randomly selects 15 of the samples to run through the water-filtration system. Afterward, she measures the contamination of all 30 samples of water, cleaning the device between each measurement.
She computes the average contamination score for the 15 samples of water that came directly from her sink, as well as the average contamination score for the 15.

What is the purpose of the random assignment?
to ensure that there are enough samples of water in each group
to ensure that the two groups of water are of equal sizes
to ensure that the two groups of water samples are roughly equivalent at the beginning of the experiment
to reduce variability in the water contamination levels

Mathematics
1 answer:
Volgvan3 years ago
4 0

Answer:

C

Step-by-step explanation:

edge 2021

You might be interested in
Find the values of the variables in the parallelogram. The diagram is not drawn to scale. Use fear rams involving parallel lines
Anarel [89]
X = 21; y = 56; z = 103
3 0
3 years ago
What’s the exact value of Cos(127.5)? Using trig identities like half angle and PLEASE EXPLAIN
vlada-n [284]

Answer:

−0.608761429

Step-by-step explanation:

use the pathagreom theorem if you have two sides subtract that from 180

8 0
3 years ago
Which number line correctly shows –0.8 + 0.6? A number line going from negative 1.6 to positive 1.6. An arrow goes from negative
Phoenix [80]

Answer:

Hi there, are you sure you didn't forget any parenthesis or signs? I can't find the right answer in the options, the one that would end up at -0.2 in the end I can edit my answer if you tell me some additional option or info about the expression I need to show on the number line

Step-by-step explanation:

which number line shows correctly -0.8 + 0.6?

well lets write it in words minus eight tenths plus six tenths\

so minus:

you go 0.8 units to the left from 0,

then plus:

you go 0.6 units right from -0.8, getting to -0.2

since there is no exact answer like that we can rearrange the addends 0.6-0.8, now:

we go from 0 6 tenths units to the right and get to 0.6, then we go from 0.6 eight tenths unit to the left to get to -0.2

4 0
3 years ago
Read 2 more answers
A patient with end-stage kidney disease has nine family members who are potential kidney donors. How many possible orders are th
eduard

Answer: 504

Step-by-step explanation:

When we select r things from n things in a order , we use permutations.

Formula for permutation:  ^nP_r=\dfrac{n!}{(n-r)!}

Given : The number of family members who are potential kidney donors. = 9

Number of people needed to be selected for best match, a second-best match, and a third-best match ( in an order)=3

Then, the number of possible orders are = ^9P_3=\dfrac{9!}{(9-3)!}

=\dfrac{9\times8\times7\times6!}{6!}=504

Hence, the number of possible orders 504.

4 0
3 years ago
True or false 49 is a irratinal number
Vikki [24]

Answer:

false

Step-by-step explanation:

49 is a rational no

brainliest pleazzzz......

7 0
3 years ago
Read 2 more answers
Other questions:
  • -15 + 8x = x+3<br> Help me please!!
    8·1 answer
  • June’s health insurance policy requires a copayment of $35 for each office visit and a copayment of $25 for each of her prescrip
    9·1 answer
  • 10. Jaylen went to the store to purchase hot dogs for a party. At the store,
    5·1 answer
  • ÐABC = 28°, and ÐBCA is larger than ÐABC. Triangle ABC is an isosceles triangle. What is the measure of the other two angles?
    9·1 answer
  • Which statement best describes the expression 3 + y ÷ 2?
    8·1 answer
  • During Sunday's game against the Nuggets, Lebron James scored 26 points. If the laker scored 105 points to win, what percentage
    9·2 answers
  • A lender is charging 2.75 points on a $275,000 loan. The borrower must therefore pay the lender an advance amount of $11,000? $6
    13·2 answers
  • The formula for the circumference of a circle is C = 2nr. Find the circumference of a
    6·1 answer
  • Pls help no links pls
    10·2 answers
  • Which of the following correctly shows the distribution of 4 in the following expression?
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!