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3 years ago

A) (s – 8) – (s + 4)

Mathematics

1 answer:

Mumz [18]3 years ago

5 0

(s-8)-(s+4) [the minus turned everything negative inside the parenthesis)

=s-8-s-4 [ + and - combines and becomes neutral, meaning turns 00, so +s and -s becomes 0]

= -12

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What is the inequality shown in the graph

rodikova [14]

It must be ≤ instead of ≥.

y ≤ - 3·x + 4

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3 years ago

Molly's Custom Kitchen Supplies sells handmade forks and spoons. It costs the store $1.70 to buy the supplies to make a fork and

Alika [10]

Answer:

3 spoons were sold last April

Step-by-step explanation:

Let x represent the total number of forks that they made last month.

Let y represent the total number of spoons that they made last month.

It costs the store $1.70 to buy the supplies to make a fork. This means that the cost of making x spoons will be 1.70×x = 1.7x

It costs the store $1.30 to buy the supplies to make a spoon. This means that the cost of making y spoons will be 1.30×y = 1.3y.

Total cost of making x forks and y spoons is 1.7x + 1.3y

Last April Molly's Custom Kitchen Supplies spent $37.90. This means that

1.7x + 1.3y = 37.90 - - - - - - - - - - 1

The store sells forks for $5.60. This means that the total amount for x forks will be 5.60×x = 5.6x

The store sells spoons for $5.40. This means that the total amount for y spoons will be 5.40×y= 5.4y.

Total amount made from selling x forks and y spoons is 5.6x + 5.4y. They sold the finished products for a total of $147.20. This means that

5.6x + 5.4y = 147.20 - - - - - - - -2

Multiplying equation 1 by 5.6 and equation 2 by 1.7, it becomes

9.52x + 7.28y = 212.24

9.52x + 9.18y = 250.24

Subtracting

- 1.9x = - 38

x = - 38/- 1.9

x = 20

Substituting x = 20 into equation 1, it becomes

1.7×20 + 1.3y = 37.90

34 + 1.3y = 37.90

1.3y = 37.90- 34 = 3.9

y = 3.9/1.3

y = 3

5 0

4 years ago

Molly spends 5 hours a week in art class. How many minutes does she spend in art class every week?

vampirchik [111]

Answer:

she spends 300 minutes in art class a week

Step-by-step explanation:

5 x 60 is 300

7 0

3 years ago

In order to estimate the difference between the average hourly wages of employees of two branches of a department store, the fol

Julli [10]

Answer:

$0.071,1.928$

Step-by-step explanation:

Downtown Store North Mall Store

Sample size n 25 20

Sample mean $\bar{x}$ $9 $8

Sample standard deviation s $2 $1

$n_1=25\\n_2=20$

$\bar{x_1}=9\\ \bar{x_2}=8$

$s_1=2\\s_2=1$

$x_1-x_2=9-8=1$

Standard error of difference of means = $\sqrt{\frac{s_1^2}{n_1}+\frac{s_2^2}{n_2}}$

Standard error of difference of means = $\sqrt{\frac{2^2}{25}+\frac{1^2}{20}}$

Standard error of difference of means = $0.458$

Degree of freedom = $\frac{\sqrt{(\frac{s_1^2}{n_1}+\frac{s_2^2}{n_2}})^2}{\frac{(\frac{s_1^2}{n_1})^2}{n_1-1}+\frac{(\frac{s_2^2}{n_2})^2}{n_2-1}}$

Degree of freedom = $\frac{\sqrt{(\frac{2^2}{25}+\frac{1^2}{20}})^2}{\frac{(\frac{2^2}{25})^2}{25-1}+\frac{(\frac{1^2}{20})^2}{20-1}}$

Degree of freedom =36

So, z value at 95% confidence interval and 36 degree of freedom = 2.0280

Confidence interval = $(x_1-x_2)-z \times SE(x_1-x_2),(x_1-x_2)+z \times SE(x_1-x_2)$

Confidence interval = $1-(2.0280)\times 0.458,1+(2.0280)\times 0.458$

Confidence interval = $0.071,1.928$

Hence Option A is true

Confidence interval is $0.071,1.928$

4 0

3 years ago

The angle of elevation of the top of a tower from a point 100m away is 45 degrees. What is the height of the tower to the neares

OLEGan [10]

<h3>Answer: 100 meters</h3>

===========================================

Explanation:

If you draw out the diagram, then you'll find that a 45-45-90 triangle forms. The nice thing about this type of triangle is that the two legs are always the same length. The horizontal leg is 100 meters, so the vertical leg must also be 100 meters.

Side note: this type of triangle is an isosceles right triangle.

---------

You could use the tangent rule to get the same thing

tan(angle) = opposite/adjacent

tan(45) = 100/x

1 = 100/x

1*x = 100

x = 100

In this case, the opposite leg is the vertical leg since it is furthest from the angle of elevation.

5 0

3 years ago

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