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3 years ago

How to do this question plz

Mathematics

1 answer:

ladessa [460]3 years ago

7 0

Answer:

number 4: frequency 8

number 5; frequency 2

Step-by-step explanation:

The mean of all rolls is their sum divided by their number, which is 30. Let x and y represent the number of rolls of 4 and 5, respectively. Then the mean is ...

(1×6 +2×3 +3×5 +4x +5y +6×6)/30 = 3.5

This simplifies to ...

(6 +6 +15 +4x +5y +36) = 3.5×30 . . . . . multiply by 30

4x +5y = 42 . . . . . . subtract 63

Of course, the total number of rolls must be 30:

6 +3 +5 +x +y +6 = 30

x + y = 10

We can solve this system of equations by substitution, using x=10-y:

4(10 -y) +5y = 42

40 +y = 42

y = 2

x = 10 -2 = 8

The two missing numbers are 8 and 2. The frequency of 4 is 8; the frequency of 5 is 2.

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Three times a number is four greater than the sum of the number and six

cestrela7 [59]

Answer:

The number is 5.

Step-by-step explanation:

Let the number be x, then:-

3x = (x + 6) + 4

3x = x+ 10

2x = 10

x = 5.

5 0

3 years ago

Edgar held a garage sale and sold a combined total of 15 toys and

raketka [301]

Answer:

He sold 6 books.

Step-by-step explanation:

If he sold a combination of 15 toys and books then the equation to find how many books he sold is the total minus how many toys he sold. 15-9=6

8 0

3 years ago

Read 2 more answers

-25/J = 5 16 + s = -90 13 + t = 51 r/10 = (-6) a + -12 =45

alexandr1967 [171]

we conclude that the solution for the given algebraic expressions are:

J = -5
s = -106
t = 38
r = -60
a = 57

<h3>How to solve these algebraic expressions?</h3>

Here we have some simple algebraic expressions:

The first one is:

-25/J = 5

We want to solve this for J.

Remember that we can perform the same operation in both sides of the equation, then we cans tart by multiplying both sides by J.

(-25/J)*J = 5*J

-25 = 5*J

Now we can divide both sides by 5, so we isolate J:

(-25)/5 = (5*J)/5

-5 = J

We conclude that the solution is J = -5.

Now, similarly for the other equations we have that:

16 + s = -90

Here we subtract 16 in both sides:

s = -90 - 16 = -106

13 + t = 51

Here we subtract 13 in both sides:

t = 51 - 13 = 38

r/10 = (-6)

Here we multiply both sides by 10:

r = (-6)*10 = -60

a + (-12) = 45

Here we add 12 in both sides:

a = 45 + 12 = 57

Then we conclude that the solution for the given algebraic expressions are:

J = -5
s = -106
t = 38
r = -60
a = 57

If you want to learn more about algebraic expressions:

brainly.com/question/4344214

#SPJ1

6 0

2 years ago

Given the data

Alexus [3.1K]

Answer:

(a) Mean = 1.6244 (b) Median = 1.65

(e) Standard deviation = 0.3325

(f) Variance = 0.1106

(g) Coefficient of variation = 20.47%.

Step-by-step explanation:

The mean (μ) of a data set is the average value of the data set. The formula to compute mean is:

$\mu=\frac{1}{n}\sum X_{i}$

The median (m) is a quantity in statistics that points out where the mid-value of a data set is. In case of, odd number of data-values, the median is given by,

$Median=(\frac{n+1}{2})^{th}\ obs.$

The mode (M) of a data set is the value that appears most often.

The range of a data-set is the difference between the maximum and minimum values in the data-set.

$Range=Max.-Min.$

The standard deviation of a data set is a numerical value that represents the amount of variation between the observed values.

$SD=\sqrt{\frac{1}{n-1}\sum (X_{i}-\mu)^{2}}$

The variance is the square of the standard deviation.

$Var=\frac{1}{n-1}\sum (X_{i}-\mu)^{2}$

The coefficient of variation (CV) is well defined as the ratio of the standard deviation to the mean. It exhibits the degree of variation in association to the mean of the population.

The formula to compute the coefficient of variation is,

$CV=\frac{\sigma}{\mu}\times 100\%$

Consider the data set provided.

(a)

Compute the mean as follows:

$\mu=\frac{1}{n}\sum X_{i}=\frac{1}{25}\times 40.61=1.6244$

Thus, the mean of the data is 1.6244.

(b)

Compute the median as follows:

Arrange the data in ascending order as follows:

0.9 , 1.05 , 1.27 , 1.3 , 1.32 , 1.35 , 1.35 , 1.42 , 1.47 , 1.47 , 1.55 , 1.63 , 1.65 ,

1.66 , 1.71 , 1.74 , 1.78 , 1.82 , 1.85 , 1.92 , 1.95 , 1.96 , 2.06 , 2.14 , 2.29

$Median=(\frac{n+1}{2})^{th}\ obs.=(\frac{25+1}{2})^{th}\ obs.=13^{th}\ obs.=1.65$

Thus, the median of the data set is 1.65.

(c)

Compute the mode as follows:

Consider the data arranged in ascending order above.

0.9 , 1.05 , 1.27 , 1.3 , 1.32 , 1.35 , 1.35 , 1.42 , 1.47 , 1.47 , 1.55 , 1.63 , 1.65 ,

1.66 , 1.71 , 1.74 , 1.78 , 1.82 , 1.85 , 1.92 , 1.95 , 1.96 , 2.06 , 2.14 , 2.29

The value 1.35 repeats twice and none of the other values repeat themselves.

Thus, the mode of the data set is 1.35.

(d)

Compute the range as follows:

$Range=Max.-Min.\\=2.29-0.90\\=1.39$

Thus, the range of the data set is 1.39.

(e)

Compute the standard deviation as follows:

$SD=\sqrt{\frac{1}{n-1}\sum (X_{i}-\mu)^{2}}=\sqrt{\frac{1}{25-1}\sum (X_{i}-1.6244)^{2}}=0.3325$

Thus, the standard deviation is 0.3325.

(f)

Compute the variance as follows:

$Var=(SD)^{2}=(0.3325)^{2}=0.1106$

Thus, the variance is 0.1106.

(g)

Compute the coefficient of variation as follows:

$CV=\frac{\sigma}{\mu}\times 100\%=\frac{0.3325}{1.6244}\times 100\%=20.47\%$

Thus, the coefficient of variation is 20.47%.

The histogram is attached below.

5 0

3 years ago

An employee compiled sales data for a company once each month. The scatter plot below shows the sales (in multiples of $1000) fo

stepan [7]

Sales aer in multipules of 1000
normally the output is y and input is x

input would be number of months
output would be the sales

so

subsitute 40 for x

y=0.94*(40)+12.5
y=37.6+12.5
y=50.1
this is in thousands
times 1000

$50,100 is the sales after 40 months

4 0

4 years ago

Read 2 more answers

How to do this question plz ​

How to do this question plz