MATHEMATICS COLLEGE

From a random sample of 41 teens, it is found that on average they spend 43.1 hours each week online with a population standard deviation of 5.91 hours. What is the 90% confidence interval for the amount of time they spend online each week?

Answers

Answer 1

Answer:

Step-by-step explanation:

We want to determine a 90% confidence interval for the mean amount of time that teens spend online each week.

Number of sample, n = 41

Mean, u = 43.1 hours

Standard deviation, s = 5.91 hours

For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.

We will apply the formula

Confidence interval

= mean +/- z ×standard deviation/√n

It becomes

43.1 ± 1.645 × 5.91/√41

= 43.1 ± 1.645 × 0.923

= 43.1 ± 1.52

The lower end of the confidence interval is 43.1 - 1.52 =41.58

The upper end of the confidence interval is 43.1 + 1.52 =44.62

Therefore, with 90% confidence interval, the mean amount of time that teens spend online each week is between 41.58 and 44.62

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Find 5 consecutive whole numbers if it is known that the sum of the squares of the first 3 numbers is equal to the sum of the squares of the last 2 numbers.

Pls answer the question important

Answers

Step-by-step explanation:

no they are not parallel

Answer:

not equal

Step-by-step explanation:

its not parallel because sum of angles of alternate angle are not equal.

Classify the following triangle as acute, obtuse, or right.
30°
249
126

Answers

Answer:

30 - Acute

249 - Obtuse

126 - Obtuse

Step-by-step explanation:

Less than 90 - Acute

90 - Right

More than 90 - Obtuse

ATTEMPT 3 OF TRYING TO GET THIS ANSWERED PLEASE HELPIn this diagram, x || y || z and m<9 = 93°.
What is the measure of each angle?

Drag and drop the correct measurements by the arrows to
match each angle.
m<2 ——>
m<4——->
m<7——->

87° 89° 91° 93 °

Answers

Answer:

m<2 = 87

m<4 = 87

m<7 = 93

Step-by-step explanation:

The concentration of DDT (C14H9Cl5), in milligrams per liter, is:(1) a nominal variable
(2) an ordinal variable
(3) an interval variable
(4) a ratio variable.

Answers

Answer:

The correct answer is (4) a ratio variable

Step-by-step explanation:

Nominal, ordinal, interval, or ratio data are the four fundamental levels of measurement scales that are used to capture data.

Nominal scales are used for labeling variables, without any quantitative value.

Ordinal the order of the values is what is significant, but the differences between each one is not really known.

Interval we know both, the order and the exact differences between the values

Ratio they have the order, the exact value between units, and have an absolute zero

In this case, the concentration of DDT (C14H9Cl5), in milligrams per liter is a RATIO, because it has order, the exact value between units, and have an absolute zero

Question 4 options:Point N is the midpoint of line GC.

If GC = 10x – 6, and NC = 3x + 5.

Find the length of line GC.

x=

GC=