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3 years ago

14

The maths test scores of 280 students are shown in the histogram below. Find the median score Find the lower quartile of the sco

res,

1 answer:

cestrela7 [59]3 years ago

4 0

Answer:

115 is the score

Step-by-step explanation:

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Recipe ingridients remain in a constant ratio no matter how many servings are prepared. Which table shows a possible ratio table

Hitman42 [59]

#of serverings: 1. 2. 3. 4. 5...

X: 4. 8. 12. 16. 20.
Y: 5. 10. 15. 20. 25.

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3 years ago

The random variable x represents the number of computers that families have along with the corresponding probabilities. Find the

Elena L [17]

Answer:

The correct option is (d).

Step-by-step explanation:

The complete question is:

The random variable x represents the number of computers that families have along with the corresponding probabilities. Use the probability distribution table below to find the mean and standard deviation for the random variable x.

x : 0 1 2 3 4

p (x) : 0.49 0.05 0.32 0.07 0.07

(a) The mean is 1.39 The standard deviation is 0.80

(b) The mean is 1.39 The standard deviation is 0.64

(c)The mean is 1.18 The standard deviation is 0.64

(d) The mean is 1.18 The standard deviation is 1.30

Solution:

The formula to compute the mean is:

$\text{Mean}=\sum x\cdot p(x)$

Compute the mean as follows:

$\text{Mean}=\sum x\cdot p(x)$

$=(0\times 0.49)+(1\times 0.05)+(2\times 0.32)+(3\times 0.07)+(4\times 0.07)\\\\=0+0.05+0.64+0.21+0.28\\\\=1.18$

The mean of the random variable x is 1.18.

The formula to compute variance is:

$\text{Variance}=E(X^{2})-[E(X)]^{2}$

Compute the value of E (X²) as follows:

$E(X^{2})=\sum x^{2}\cdot p(x)$

$=(0^{2}\times 0.49)+(1^{2}\times 0.05)+(2^{2}\times 0.32)+(3^{2}\times 0.07)+(4^{2}\times 0.07)\\\\=0+0.05+1.28+0.63+1.12\\\\=3.08$

Compute the variance as follows:

$\text{Variance}=E(X^{2})-[E(X)]^{2}$

$=3.08-(1.18)^{2}\\\\=1.6876$

Then the standard deviation is:

$\text{Standard deviation}=\sqrt{\text{Variance}}$

$=\sqrt{1.6876}\\\\=1.2990766\\\\\approx 1.30$

Thus, the mean and standard deviation for the random variable x are 1.18 and 1.30 respectively.

The correct option is (d).

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3 years ago

8.25 equals how many ones?

prohojiy [21]

Answer:

i think 20.95 centimetres

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3 years ago

You sign up for karate classes. The classes are $80 per month.

maria [59]

The amount of dollars you pay for each month can be shown by d=80m

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4 years ago

Read 2 more answers

The greatest common factor of −27x2yz5 + 15x3z3

Goryan [66]

We have that
−27x2yz5 + 15x3z3

we know that
27-------------> 3³
15-------------> 3*5
z^5-----------> z² * z³
x³------------> x² * x

substituting in the original expression<span>

−27x2yz5 + 15x3z3---------->[-3</span>³*x²*y*z³*z²]+[3*5*x²*x*z³]

[-3³*x²*y*z³*z²]+[3*5*x²*x*z³]-------> [3*x² *z³]*{[-3² *y*z²]+[5*x]}

the greatest common factor is [3*x² *z³]

8 0

3 years ago