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4 years ago

How do you solve this equation -91=-7(n+6)

2 answers:

6 0

The first thing you do is distribute. So multiply -7 to n and 6 to get -7n-42=-91 add over -42 to -91 to get -7n=-133 then divide by 7 on both sides and you get n=19

pishuonlain [190]4 years ago

3 0

-91=-7(n+6) step 1: distribute -7 to n and 6
-91=-7n+(-42) step 2: add 42 to both sides
-91+42=-7n+(-42)+42
-49=-7n step 3: divide both sides by -7
-49/-7=-7n/-7
7=n

You might be interested in

11) -6x – 9y = 0<br> -24x = 36y

arlik [135]

Answer:

x = 0, y = 0

(0, 0)

Step-by-step explanation:

-24x - 36y = 0

divide the equation by 4

-8x - 9y = 0

-6x - 9y = 0

multiply the second equation by -1

6x + 9y = 0

add them together

-8x - 9y = 0

6x + 9y = 0

-2x = 0

x = 0

substitute into the second equation

-8 * 0 - 9y = 0

-9y = 0

y = 0

5 0

3 years ago

What is the equation of the line that passes through the point (-3,6) and has a slope of -2

OverLord2011 [107]

Answer:

pls

Step-by-step explanation:

3 0

3 years ago

Curtis threw 15 darts at a dartboard. 40% of his darts hit the bull's-eye. How many darts did not hit the bull's-eye?

ValentinkaMS [17]

<span>Curtis threw 15 darts at a dartboard. 40% of his darts hit the bull's-eye.
Let’s find out how many darts did not hit the bull's-eye.
=> 15 darts = 100%
=> 40% of 15 hits bull’s eye.
Now let’s solve:
=> 40% / 100% = .40
we need to get the 40% value of 15 to know how many darts was able to hit bull’s eye.
=> 15 * .40 = 6 darts
Thus, out of 15, 6 of the darts hit bull’s eye,.</span>

6 0

3 years ago

A simple random sample of size nequals=8181 is obtained from a population with mu equals 77μ=77 and sigma equals 27σ=27. (a) De

ivanzaharov [21]

Answer:

a) $P(\bar X>81.5)=1-0.933=0.067$

b) $P(\bar X$

c) $P(73.4$

Step-by-step explanation:

1) Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Let X the random variable that represent interest on this case, and for this case we know the distribution for X is given by:

$X \sim N(\mu=77,\sigma=27)$

And let $\bar X$ represent the sample mean, the distribution for the sample mean is given by:

$\bar X \sim N(\mu,\frac{\sigma}{\sqrt{n}})$

On this case $\bar X \sim N(77,\frac{27}{\sqrt{81}})$

Part a

We want this probability:

$P(\bar X>81.5)=1-P(\bar X$

The best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}$

If we apply this formula to our probability we got this:

$P(\bar X >81.5)=1-P(Z$

$P(\bar X>81.5)=1-0.933=0.067$

Part b

We want this probability:

$P(\bar X\leq 69.5)$

If we apply the formula for the z score to our probability we got this:

$P(\bar X \leq 69.5)=P(Z\leq \frac{69.5-77}{\frac{27}{\sqrt{81}}})=P(Z$

$P(\bar X\leq 69.5)=0.0062$

Part c

We are interested on this probability

$P(73.4$

If we apply the Z score formula to our probability we got this:

$P(73.4$

$=P(\frac{73.4-77}{\frac{27}{\sqrt{81}}}$

And we can find this probability on this way:

$P(-1.2$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(-1.2$

3 0

4 years ago

an amusement park line is moving about 4 feet every 15 minutes at this rate approximately how long will it take for a person at

Natasha_Volkova [10]

4/15 = 50/x...4 ft to 15 min = 50 ft to x minutes
this is a proportion, so we cross multiply
(4)(x) = (15)(50)
4x = 750
x = 750/4
x = 187.5 minutes or 3 hrs and 7.5 minutes

or u can do it this way..
15/4 = 3.75 ft per minute......50 * 3.75 = 187.5 minutes

3 0

4 years ago