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
erastovalidia [21]
3 years ago
13

In a sample of students, 12 out of 24 students in a class wanted a sandwich for lunch. Using the data from the sample, predict h

ow many students would want sandwiches for lunch in a school of 400
Mathematics
1 answer:
Alona [7]3 years ago
3 0
12 of 24 = 50%

50% of 400 = 200

Your answer is 200.
You might be interested in
"An ordinance requiring that a smoke detector be installed in all previously constructed houses has been in effect in a particul
Galina-37 [17]

Answer:

a) Probability that the claim is rejected when the actual value of p is 0.8 = P(X ≤ 15) = 0.0173

b) Probability of not rejecting the claim when p = 0.7, P(X > 15) = 0.8106

when p = 0.6, P(X > 15) = 0.4246

c) Check Explanation

The error probabilities are evidently lower when 15 is replaced with 14 in the calculations.

Step-by-step explanation:

p is the true proportion of houses with smoke detectors and p = 0.80

The claim that 80% of houses have smoke detectors is rejected if in a sample of 25 houses, not more than 15 houses have smoke detectors.

If X is the number of homes with detectors among the 25 sampled

a) Probability that the claim is rejected when the actual value of p is 0.8 = P(X ≤ 15)

This is a binomial distribution problem

A binomial experiment is one in which the probability of success doesn't change with every run or number of trials (probability that each house has a detector is 0.80)

It usually consists of a number of runs/trials with only two possible outcomes, a success or a failure (we are sampling 25 houses with each of them either having or not having a detector)

The outcome of each trial/run of a binomial experiment is independent of one another.

Binomial distribution function is represented by

P(X = x) = ⁿCₓ pˣ qⁿ⁻ˣ

n = total number of sample spaces = 25 houses sampled

x = Number of successes required = less than or equal to 15

p = probability of success = probability that a house has smoke detectors = 0.80

q = probability of failure = probability that a house does NOT have smoke detectors = 1 - p = 1 - 0.80 = 0.20

P(X ≤ 15) = Sum of probabilities from P(X = 0) to P(X = 15) = 0.01733186954 = 0.01733

b) Probability of not rejecting the claim when p= 0.7 when p= 0.6

For us not to reject the claim, we need more than 15 houses with detectors, hence, th is probability = P(X > 15), but p = 0.7 and 0.6 respectively for this question.

n = total number of sample spaces = 25 houses sampled

x = Number of successes required = more than 15

p = probability that a house has smoke detectors = 0.70, then 0.60

q = probability of failure = probability that a house does NOT have smoke detectors = 1 - p = 1 - 0.70 = 0.30

And 1 - 0.60 = 0.40

P(X > 15) = sum of probabilities from P(X = 15) to P(X = 25)

When p = 0.70, P(X > 15) = 0.8105639765 = 0.8106

When p = 0.60, P(X > 15) = 0.42461701767 = 0.4246

c) How do the "error probabilities" of parts (a) and (b) change if the value 15 in the decision rule is replaced by 14.

The error probabilities include the probability of the claim being false.

When X = 15

(Error probability when p = 0.80) = 0.0173

when p = 0.70, error probability = P(X ≤ 15) = 1 - P(X > 15) = 1 - 0.8106 = 0.1894

when p = 0.60, error probability = 1 - 0.4246 = 0.5754

When X = 14

(Error probability when p = 0.80) = P(X ≤ 14) = 0.00555

when p = 0.70, error probability = P(X ≤ 14) = 0.0978

when p = 0.60, error probability = P(X ≤ 14) = 0.4142

The error probabilities are evidently lower when 15 is replaced with 14 in the calculations.

Hope this Helps!!!

6 0
3 years ago
A new coffee shop is opening and plans to sell cups of coffee at $4 each. It costs $3 to make each cup of coffee, and the shop n
never [62]

Answer:

the answer is b

Step-by-step explanation:

6 0
2 years ago
Suppose you deposit $1,200 into a bank account. The account earns yearly simple interest at a rate of 1 3/4%. How many years wil
igor_vitrenko [27]

Answer:

6 years

Step-by-step explanation:

1.75% of 1,200 = 21

so 1 year= 21

21+21= 42         2 years

42+21=63           3 years

63+21=84            4 years

81+21=105             5 years

105+21=126            6 years

Or you can do

21x6=126 so it has to equal 6 years

4 0
2 years ago
I need help please answer correctly
Bas_tet [7]

Answer:

AC

Step-by-step explanation:

5 0
2 years ago
Read 2 more answers
A population has a mean of 300 and a standard deviation of 40. Suppose a sample of size 100 is selected and is used to estimate
bazaltina [42]

Answer:

a: 0.9544 9 within 8 units)

b: 0.9940

Step-by-step explanation:

We have µ = 300 and σ = 40.  The sample size, n = 100.  

For the sample to be within 8 units of the population mean, we would have sample values of 292 and 308, so we want to find:

P(292 < x < 308).

We need to find the z-scores that correspond to these values using the given data.  See attached photo 1 for the calculation of these scores.

We have P(292 < x < 308) = 0.9544

Next we want the probability of the sample mean to be within 11 units of the population mean, so we want the values from 289 to 311.  We want to find

P(289 < x < 311)

We need to find the z-scores that correspond to these values.  See photo 2 for the calculation of these scores.

We have P(289 < x < 311) = 0.9940

5 0
3 years ago
Other questions:
  • 17 1/3 + (-50 1/3) -5 1/2
    13·2 answers
  • John inherited $25,000 and invested part of it in a money market account, part in municipal bonds, and part in a mutual fund. Af
    9·1 answer
  • 8j - k + 14 when j = 0.25 and k = 1
    8·2 answers
  • What percentage of 67.5 is 7.02?<br><br> 27 is 144% of what?
    7·1 answer
  • Can some one tell me how to Divide this very big Question You will be a life savor if you do!!!!!!
    10·1 answer
  • Canned green beans are on sale 5 cans for $3.00. Write an equation to represent how many csns of green beans Mrs.o'conner could
    12·2 answers
  • X3−3=x9+3 what the answer
    7·1 answer
  • Write a linear function f with f(0) = 7 and f(3) =1.
    5·1 answer
  • Factor this expression completely.<br> 6x^2- 13x - 28
    13·2 answers
  • Use the distributive property to remove the parentheses.<br> -3(-6y +3w-2)
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!