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
sweet [91]
3 years ago
8

A manufacturer claims that its new hand sanitizer reduces the number of days an average person is sick in a year. To test this c

laim, a researcher decided to conduct an experiment. The researcher randomly selected 300 people, divided into subject groups by age. Over the course of a year, all the subjects regularly used the hand sanitizer. At the end of the year, the researcher compared the number of days that the subjects in each group were sick.
Which statements about this experiment are true?

Mathematics
2 answers:
Andrew [12]3 years ago
5 0

Answer:

The study uses blocking and random sampling.

Step-by-step explanation:

marysya [2.9K]3 years ago
3 0

Answer:

in my opinion is the last:

this studies uses a control group

Step-by-step explanation:

You might be interested in
At what rate per annum ci will RS 2000 amount to RS 2315.35 in 3 years
Mashutka [201]

<u>ANSWER: </u>

Rate per annum at which CI will amount from RS 2000 to RS 2315.35 in 3 years is 5%

<u>SOLUTION: </u>

Given,  

P = RS 2000

C.I = RS 2315.35

T = 3 years

We need to find the rate per annum. i.e. R = ?

We know that,  

When interest is compound Annually:

Amount $=\mathrm{P}\left(1+\frac{\mathrm{R}}{100}\right)^{n}$

Where p = principal amount

r = rate of interest

n = number of years

$2315.35=2000 \times\left(1+\frac{R}{100}\right)^{3}$

$\left(1+\frac{R}{100}\right)^{3}=\frac{2315.35}{2000}$

$\left(1+\frac{R}{100}\right)^{3}=1.157$

$1+\frac{R}{100}=\sqrt[3]{1.157}$

$1+\frac{R}{100}=1.0500$

$\frac{R}{100}=1.05-1$

$\frac{R}{100}=0.05$

R = 5%

Hence, rate per annum is 5 percent.

3 0
3 years ago
Find the area of the shaded region.
Citrus2011 [14]

Answer:

pi × 18cm^2

Or approximately,

56.52cm^2 (using 3.14 for pi)

or

56.5487cm^2 (using pi button on calculator)

Step-by-step explanation:

Area of a circle is pi times [radius squared].

All circles are 360°.

Problem can be solved by finding area of whole circle, and then using ratios.

Whole Circle: area = pi × (9cm)^2 = pi × 81cm^2

80° / 360° = Area[shaded] / (pi × 81cm^2)

pi × 18cm^2 = Area[shaded]

((If you read my answer before the edit, I am sorry. I made a calculator error.))

3 0
3 years ago
What is the domain of the function using the graph?
Fofino [41]

The answer is B) x is equal to all real numbers.

The domain of a function is the numbers for x that you can put in. Although the y-values are restricted here, you can put any number you want in for x. Therefore, x is equal to all real numbers.

6 0
4 years ago
Jenny bought a pair of pants for $19.99 and two shirts for $7.50. If she gave the cashier 40 dollars how much change did she rec
VMariaS [17]

Answer:

Jenny will receive $12.51 in change.

Step-by-step explanation:

We need to find the total cost first.

19.99 + 7.50 = 27.49

We then subtract that from the 40 dollars she gave to get the amount of change she receives.

40.00 - 27.49 = 12.51.

She will receive $12.51 in change.

hope this helped!  

4 0
3 years ago
Find the area of the equilateral triangle when the base is 2.0 cm and the top angle is 50°
nordsb [41]

Answer:

There is an error in the question.

All angles in an equilateral triange are 60º

3 0
3 years ago
Other questions:
  • Elise said that 0.2 equals 2. Use words and numbers to explain her mistake.
    9·1 answer
  • What is 10÷5/8 in a math order.
    13·1 answer
  • 3x + 1 &lt; −2x + 8
    12·1 answer
  • Question 42 points)<br> Tell whether the triangles<br> are similar.<br> Yes or No
    15·2 answers
  • Y = 4x - 7 <br> What is the y-intercept?
    7·1 answer
  • PLEASE HELP!!!!!! A linear function has a y-intercept of -12 and a slope of 3/2. What is the equation of the line?
    12·2 answers
  • HELPP ASAPP PLEASEEE
    5·1 answer
  • Cuanto da √(1 ÷ 6^2 - 1 ÷ 10^2)
    11·1 answer
  • Estimate each quotient:
    14·1 answer
  • What is an equation of the line that passes through the points (-3,1) and (-4,0)
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!