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3 years ago

I just need a step by step expiation please!

Mathematics

1 answer:

aniked [119]3 years ago

6 0

Answer:

first I would combine terms which would give me

-4x-7=-7-4x

then I would get the variable on each side of the equal sign

0=0

lastly I would verify the solution

infinite solutions

Step-by-step explanation:

combining combining like terms would give you negative 4x - 7 which is equal to -7 - 4x. if you were to add 7 on either side and 4 on either side you would get 0 = 0 because this is correct it's infinite solutions

You might be interested in

License plates are made using 3 letters followed by 2 digits. How many plates can be made if repetition of letters and digits is

Helga [31]

Answer:

$26^3\times10^2 = 1757600$

option B is correct

Step-by-step explanation:

We have 5 spaces in the license plate:

_ _ _ _ _

we have 26 available letters, and 10 available numbers.

starting with letters:

how many choices do i have to place the 1st letter? 26.

26 _ _ _ _

how many choices do i have to place the 2nd letter? 26 (since we're allowed to repeat letters)

26 26 _ _ _

how many choices do i have to place the 3rd letter? 26

26 26 26 _ _

we've used all the places for letters, (note: the exact position of the letters doesn't matter here, the first letter could've been placed anywhere in _ _ _ _ _, but the amount of possible choices for letters would always be 26).

let's move on to numbers.

how many choices do i have to place the 1st number? 10

26 26 26 10 _

how many choices do i have to place the 2nd number? 10

26 26 26 10 10

we've completed our number plate. Next we'll simply multiply all these numbers to get all the possible arrangements in which numbers and letters can be displayed on a license place.

$26^3\times10^2 = 1757600$

option B is correct

8 0

3 years ago

Y= -4x cos(x) -5

saw5 [17]

To be honest I do t understand this but Carlos does so contact him

3 0

3 years ago

What fraction is greater than 2/3

lutik1710 [3]

2/3 is basically 0.6666666667 which is the same as 66% so any percentage bigger than 66% such as 75% (0.75) which is 3/4 (as a fraction) is bigger than 2/3

8 0

3 years ago

3/9+2/9=?/9 Help a brother out

Ahat [919]

Answer:

5/9

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

The manager of a computer retails store is concerned that his suppliers have been giving him laptop computers with lower than av

34kurt

Answer:

Probability that the 50 randomly selected laptops will have a mean replacement time of 3.1 years or less is 0.0092.

Yes. The probability of this data is unlikely to have occurred by chance alone.

Step-by-step explanation:

We are given that the replacement times for the model laptop of concern are normally distributed with a mean of 3.3 years and a standard deviation of 0.6 years.

He then randomly selects records on 50 laptops sold in the past and finds that the mean replacement time is 3.1 years.

Let M = sample mean replacement time

The z-score probability distribution for sample mean is given by;

Z = $\frac{ M-\mu}{\frac{\sigma}{\sqrt{n} } }} }$ ~ N(0,1)

where, $\mu$ = population mean replacement time = 3.3 years

$\sigma$ = standard deviation = 0.6 years

n = sample of laptops = 50

The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.

Now, Probability that the 50 randomly selected laptops will have a mean replacement time of 3.1 years or less is given by = P(M $\leq$ 3.1 years)

P(M $\leq$ 3.1 years) = P( $\frac{ M-\mu}{\frac{\sigma}{\sqrt{n} } }} }$ $\leq$ $\frac{ 3.1-3.3}{\frac{0.6}{\sqrt{50} } }} }$ ) = P(Z $\leq$ -2.357) = 1 - P(Z $\leq$ 2.357)

= 1 - 0.99078 = 0.0092 or 0.92%

So, in the z table the P(Z $\leq$ x) or P(Z < x) is given. So, the above probability is calculated by looking at the value of x = 2.357 in the z table which will lie between x = 2.35 and x = 2.36 which has an area of 0.99078.

Hence, the required probability is 0.0092 or 0.92%.

Now, based on the result above; Yes, the computer store has been given laptops of lower than average quality because the probability of this data is unlikely to have occurred by chance alone as the probability of happening the given event is very low as 0.92%.

8 0

3 years ago