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mariarad [96]
3 years ago
8

If the ratio of a circle's sector to its total area is 1/3, what is the measure of

Mathematics
1 answer:
nalin [4]3 years ago
4 0

Answer:

option A:  120°

Step-by-step explanation:

Area \ of \ circle = \pi r^2\\\\Area \ of \ sector = \pi r^2 \frac{ \theta}{360}\\\\Ratio \ of \ sector \ to \ circle = \frac{1}{3}\\\\That is, \\\frac{1}{3} = \frac{\pi r^2 \frac{\theta}{360}} {\pi r^2}\\\\\\\frac{1}{3} = \frac{\theta}{360} \\\\\frac{360}{3} = \theta\\\\120 = \theta

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Ostrovityanka [42]

Answer:

a) The study is an observational study

b) The proportion of children with significant social activity in children with acute lymphoblastic leukemia is approximately 0.802

The proportion of children with significant social activity in children without acute lymphoblastic leukemia is approximately 0.8565

c) The odds ratio is approximately 0.6780

d) The 95% CI is approximately 0.523 < OR < 0.833

e) i) Yes

ii) Children with more social activity have a higher occurrence of acute lymphoblastic leukemia

Step-by-step explanation:

a) An experimental study is a study in which the researcher adds inputs to the study and then monitors the outcomes

An observational study is one in which the researcher observes risk factors and does not intervene in the process

Therefore, the study is an observational study

b) The proportion of children with significant social activity in children with acute lymphoblastic leukemia is \hat p_1 = 1020/1272 = 85/106 = 0.8\overline {0188679245283} ≈ 0.802

The proportion of children with significant social activity in children without acute lymphoblastic leukemia is \hat p_2 = 5343/6238 ≈ 0.8565

c) We have the following two way table;

\begin{array}{ccc}Lymphoblastic \ Leukemia &With \ Social \ Activity & Without \ Social \ Activity\\With&1020 \ (a)&252 \ (b)\\Without&5343 \ (c)&895 \ (d) \end{array}

The \ odds \ ratio = \dfrac{1,020 \times 895}{5,343 \times 252} \approx 0.6780

The odds ratio ≈ 0.6780

d) The 95% confidence interval for the odds ratio is given as follows;

95 \% \ CI = OR \ \pm \ 1.96 \times \sqrt{\dfrac{1}{a} +\dfrac{1}{b}+\dfrac{1}{c}+\dfrac{1}{d}}

Where;

a = 1020, b = 252, c = 5343, d = 895

Therefore;

95 \% \ CI \approx  0.6780 \ \pm \ 1.96 \times \sqrt{\dfrac{1}{1,020} +\dfrac{1}{252}+\dfrac{1}{5,343}+\dfrac{1}{895}} \approx 0.678 \pm0.155

The 95% CI ≈ 0.523 < OR < 0.833

e) i) Given that the observed Odds Ratio is within the Confidence Interval, therefore, there is an indication that the amount of social activity is associated with acute lymphoblastic leukemia

ii) Based on the proportion of the study findings, children with more social activity have a higher occurrence of acute lymphoblastic leukemia

6 0
2 years ago
Write the percent shown by each model. Explain your reasoning.
Sphinxa [80]
A) 1/3=33 1/3%
B) 2/3=66 2/3%
C) 1/6=16 2/3%

A) YOU CAN TURN THE FRACTION 1/3 INTO A DECIMAL WHICH WILL BE AROUND 0.333. THEN YOU TURN THE DECIMAL INTO A PERCENT. YOU CAN MOVE THE DECIMAL TWO PLACES TO THE RIGHT. THAT GIVES YOU 33.3% OR 33 1/3% THIS ALSO APPLIES TO B BUT WITH 0.666 AND 66.6%

FOR C, YOU DO THE SAME. 1/6 AS A DECIMAL IS 1.666. YOU MOVE THE DECIMAL TWO PLACES TO THE RIGHT. 16.6% OR 16 2/3%


HOPE THIS HELPED.
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