I need help plz !!!!!!!

which property is illustrated by the equation below (r+s)+t=r+(s+t). A)Associative B)Commutative C)Distributive D)Identity

Lera25 [3.4K]

The associative property of addition is being demonstrated here. The parenthesis are moved around to "associate" or "group" the values into two different pairs.

Note: the associative property of multiplication is very similar and it is
a*(b*c) = (a*b)*c

4 0

3 years ago

A study has indicated that the sample size necessary to estimate the average electricity use by residential customers of a large

Zanzabum

Answer:

$\sigma=547.1125$

Step-by-step explanation:

-The margin of error is calculated using the formula:

$ME=z_{\alpha/2}\times \frac{\sigma}{\sqrt{n}}\\\\$

-We substitute the values, n=900 and ME=30 in the formula to solve for standard deviation:

$ME=z_{\alpha/2}\times \frac{\sigma}{\sqrt{n}}\\\\\\30=1.645\times\frac{\sigma}{\sqrt{900}}\\\\\sigma=\frac{30^2}{1.645}\\\\=547.1125$

Hence, the population standard deviation is 547.1125

7 0

3 years ago

House of Mohammed sells packaged lunches, where their finance department has established a

blagie [28]

The revenue function is a quadratic equation and the graph of the function

has the shape of a parabola that is concave downwards.

The correct responses are;

(a) R = -x² + 82·x

(b) $1,645

(c) The graph of R has a maximum because the leading coefficient of the quadratic function for R is negative.

(d) R = -1·(x - 41)² + 1,681

(e) 41

(f) $1,681

Reasons:

The given function that gives the weekly revenue is; R = x·(82 - x)

Where;

R = The revenue in dollars

x = The number of lunches

(a) The revenue can be written in the form R = a·x² + b·x + c by expansion of the given function as follows;

R = x·(82 - x) = 82·x - x²

Which gives;

R = -x² + 82·x

Where, the constant term, c = 0

(b) When 35 launches are sold, we have;

x = 35

Which by plugging in the value of x = 35, gives;

R = 35 × (82 - 35) = 1,645

The revenue when 35 lunches are sold, R = $1,645

(c) The given function for R is R = x·(82 - x) = -x² + 82·x

Given that the leading coefficient is negative, the shape of graph of the

function R is concave downward, and therefore, the graph has only a

maximum point.

(d) The form a·(x - h)² + k is the vertex form of quadratic equation, where;

(h, k) = The vertex of the equation

a = The leading coefficient

The function, R = x·(82 - x), can be expressed in the form a·(x - h)² + k, as follows;

R = x·(82 - x) = -x² + 82·x

At the vertex, of the equation; f(x) = a·x² + b·x + c, we have;

$\displaystyle x = \mathbf{-\frac{b}{2 \cdot a}}$

Therefore, for the revenue function, the x-value of the vertex, is; $\displaystyle x = -\frac{82}{2 \times (-1)} = \mathbf{41}$

The revenue at the vertex is; $R_{max}$ = 41×(82 - 41) = 1,681

Which gives;

(h, k) = (41, 1,681)

a = -1 (The coefficient of x² in -x² + 82·x)

The revenue equation in the form, a·(x - h)² + k is; R = -1·(x - 41)² + 1,681

(e) The number of lunches that must be sold to achieve the maximum revenue is given by the x-value at the vertex, which is; x = 41

Therefore;

The number of lunches that must be sold for the maximum revenue to be achieved is 41 lunches

(f) The maximum revenue is given by the revenue at the vertex point where x = 41, which is; R = $1,681

The maximum revenue of the company is $1,681

Learn more about the quadratic function here:

brainly.com/question/2814100

6 0

2 years ago

Please help if you can Thank you so much!

Vladimir [108]

Answer:

Answers in explanations, hope they're correct!

Step-by-step explanation:

12. You will be using 0 gallons of gas when traveling 0 miles.

13. 20 gallons

14. (2,6)

15. You will package 15 dozens of cupcakes after 5 hours

4 0

3 years ago

Read 2 more answers

Tires have a normal distribution with a mean of 70000 miles and a standard deviation of 4400 miles. What proportion of tires wil

yarga [219]

Let T = the distance, in miles, a tire lasts

T ~ N(70000,4400²)

P(T $\geq$ 75000)
= P(Z $\geq \frac{75000 - 70000}{4400}$ )
= P(Z $\geq \frac{25}{22}$ )
≈ P(Z $\geq$ 1.14)
= 1 - P(Z < 1.14)
≈ 1 - 0.8729
= 0.1271

5 0

3 years ago