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2 years ago

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44 students completed some homework and the histogram shows information about the times taken. Work out an estimate of the inter

quartile range. In your working you must show the lower and upper quartiles

1 answer:

MAXImum [283]2 years ago

6 0

1.4×5=7

0.8×10=8

1.4×10=14

1×15=15

15+14+8+7=44

44÷4=11

LQ of 44=11

LQ=10 minutes

11×3=33

UQ= 29 minutes

The Range is 19 minutes

Step-by-step explanation:

Start with the separate boxes. So to work out the real number of students in each bracket, we do Frequency density × The difference in the bracket. (so if its 5-15 then the difference is 10)

This leads us to have the amounts of students in each bracket.

Then work out the LQ of 44 and its 11.

Then find where the 11th student's result is and in this case its in the 5-15. There is 7 already passed and 8 in 5-15. This means that the 11th is in the middle of 5-15 as 7+4=11. The middle of 5-15 is 10.

Repeat this for the UQ.

The range is UQ-LQ so 29-10=19 minutes.

Hope this helps, i'm not fully sure whether this makes sense and i've no clue what the things ive called brackets are actually called.

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Answer:

1184000

Step-by-step explanation:

lcm(2960,6400,2000)

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Take the largest power of each factor:

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1 year ago

Consider the continuous random variable X, which has a uniform distribution over the interval from 20 to 28.

anastassius [24]

Answer:

a) The probability distribution is $f(x) = \frac{1}{8}$

b) 0.5 = 50% probability that X will take on a value between 21 and 25.

c) 0.25 = 25% probability that X will take on a value of at least 26.

Step-by-step explanation:

Uniform probability distribution:

An uniform distribution has two bounds, a and b.

The probability of finding a value of at lower than x is:

$P(X < x) = \frac{a - x}{b - a}$

The probability of finding a value between c and d is:

$P(c \leq X \leq d) = \frac{d - c}{b - a}$

The probability of finding a value above x is:

$P(X > x) = \frac{b - x}{b - a}$

Uniform distribution over the interval from 20 to 28.

This means that $a = 20, b = 28$

a. What’s the probability density function?

The probability density function of the uniform distribution is:

$f(x) = \frac{1}{b - a}$

In this question:

$f(x) = \frac{1}{28 - 20} = \frac{1}{8}$

b. What’s the probability that X will take on a value between 21 and 25?

$P(21 \leq X \leq 25) = \frac{25 - 21}{28 - 20} = \frac{4}{8} = 0.5$

0.5 = 50% probability that X will take on a value between 21 and 25.

c. What’s the probability that X will take on a value of at least 26?

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2 years ago

A group of kids just finished trick-or-treating. The number of pieces of candy collected by each of the 5 kids

NemiM [27]

Answer:

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$s =\sqrt{\frac{(31-35)^2 +(33-35)^2 +(36-35)^2 +(41-35)^2 +(34-35)^2}{5-1}} =3.808$

And the answer for this case would be :

$s= 3.81$ after round the value

Step-by-step explanation:

We have the following data set given:

31, 33, 36, 41, 34

If we want to find the standard deviation we need to find first the sample mean with this formula:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

And replacing we got:

$\bar X = \frac{31+33+36+41+34}{5}= \frac{175}{5}= 35$

Now we can find the sampel deviation with this formula:

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

And replacing we got:

$s =\sqrt{\frac{(31-35)^2 +(33-35)^2 +(36-35)^2 +(41-35)^2 +(34-35)^2}{5-1}} =3.808$

And the answer for this case would be :

$s= 3.81$ after round the value

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2 years ago

The probabilities of the orphaned pets in six cities' animal shelters being different types of animals are given in the table. I

olga2289 [7]

Given the table below showing t<span>he probabilities of the orphaned pets in six cities' animal shelters being different types of animals.

</span>
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                         −Lhasa Apso −Mastiff −Chihuahua −Collie
Austin       24.5%      2.76%    2.86%     3.44%    2.65%
Baltimore 19.9%      3.37%    3.22%     3.31%    2.85%
Charlotte 33.7%     3.25%     3.17%     2.89%    3.33%
St. Louis 43.8%     2.65%     2.46%     3.67%    2.91%
Salt Lake
City          28.9%     2.85%     2.78%     2.96%    2.46%
Orlando   37.6%     3.33%     3.41%     3.45%    2.78%
Total        22.9%     2.91%     2.68%     3.09%    2.58%</span><span>

Condtional probability </span><span>is a measure of the probability of an event given that another event has occurred. If the event of interest is A and the event B is known or assumed to have occurred, "the conditional probability of A given B", or "the probability of A under the condition B", is usually written as P(A|B).

The probability of A given B, is given by
$P(A|B)= \frac{P(A\cap B)}{P(B)}$

From the table, the probability that an </span>orphaned pet in a St. Louis animal shelter is a mastiff dog is 2.46% and the probability that <span>an <span>orphaned pet in a St. Louis animal shelter is a dog is 2.91% + 2.68% + 3.09% + 2.58% = 11.26%</span>

The probability that a randomly selected orphaned pet in a St. Louis animal shelter is a mastiff given that it is a dog, is given by
$\frac{P(St. \, Louis\, and\, dog-mastiff)}{P(dog)} = \frac{2.46}{11.26} \times100\%=21.85\%$ </span>

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2 years ago

Read 2 more answers

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lorasvet [3.4K]

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