All categories

2 years ago

Please explain what this means! (no math needs to be done as I got the answers but I don't understand the explanation...)

Mathematics

1 answer:

nata0808 [166]2 years ago

6 0

you can imagine this as a venn diagram. the "or" event would consist of everything in both sides and the middle of the venn diagram because you can choose form either event x or event y.

the "and" event would consist of everything in the middle of the venn diagram because you choice must be a part of both event x and event y.

the complement of an event is just everything that is not included in the event. for example, in a coin flip, the complement of heads is tails. in a dice roll, the complement of {1,2} is {3,4,5,6}

so if you come across these just think "either or" or "both and." and remember that the complement is everything excluding what is listed.

i apologize if this does not help, im not that great at explaining things

You might be interested in

Is 60.43 an irrational number

zhuklara [117]

Answer:

No, It is rational

Step-by-step explanation:

An number with a finite number of decimal point/numbers can be rational unlike numbers that repeat on forever like the number pi

4 0

2 years ago

The given matrix is the augmented matrix for a linear system. Use technology to perform the row operations needed to transform t

shtirl [24]

Answer:

$x_{1} = \frac{176}{127} + \frac{71}{127}x_{4}\\\\ x_{2} = \frac{284}{127} + \frac{131}{254}x_{4}\\\\x_{3} = \frac{845}{127} + \frac{663}{254}x_{4}\\$

Step-by-step explanation:

As the given Augmented matrix is

$\left[\begin{array}{ccccc}9&-2&0&-4&:8\\0&7&-1&-1&:9\\8&12&-6&5&:-2\end{array}\right]$

Step 1 :

$r_{1}$ ↔ $r_{1} - r_{2}$

$\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&7&-1&-1&:9\\8&12&-6&5&:-2\end{array}\right]$

Step 2 :

$r_{3}$ ↔ $r_{3} - 8r_{1}$

$\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&7&-1&-1&:9\\0&124&-54&77&:-82\end{array}\right]$

Step 3 :

$r_{2}$ ↔ $\frac{r_{2}}{7}$

$\left[\begin{array}{ccccc}1&-14&6&-9&:10\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&124&-54&77&:-82\end{array}\right]$

Step 4 :

$r_{1}$ ↔ $r_{1} + 14r_{2}$ , $r_{3}$ ↔ $r_{3} - 124r_{2}$

$\left[\begin{array}{ccccc}1&0&4&-11&:-8\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&0&- \frac{254}{7} &\frac{663}{7} &:-\frac{1690}{7} \end{array}\right]$

Step 5 :

$r_{3}$ ↔ $\frac{r_{3}. 7}{254}$

$\left[\begin{array}{ccccc}1&0&4&-11&:-8\\0&1&-\frac{1}{7} &-\frac{1}{7} &:\frac{9}{7} \\0&0&1&-\frac{663}{254} &:-\frac{1690}{254} \end{array}\right]$

Step 6 :

$r_{1}$ ↔ $r_{1} - 4r_{3}$ , $r_{2}$ ↔ $r_{2} + \frac{1}{7} r_{3}$

$\left[\begin{array}{ccccc}1&0&0&-\frac{71}{127} &:\frac{176}{127} \\0&1&0&-\frac{131}{254} &:\frac{284}{127} \\0&0&1&-\frac{663}{254} &:\frac{845}{127} \end{array}\right]$

∴ we get

$x_{1} = \frac{176}{127} + \frac{71}{127}x_{4}\\\\ x_{2} = \frac{284}{127} + \frac{131}{254}x_{4}\\\\x_{3} = \frac{845}{127} + \frac{663}{254}x_{4}\\$

6 0

2 years ago

in 2010 an enormous sinkhole suddenly appeared in the middle of a guatemalan neighborhood and swallowed a three story building a

Leokris [45]

Answer:

Step-by-step explanation:

Given that :

The enormous sinkhole that appeared in the middle of Guatemalan neighborhood in the year 2010 swallowed a three story building above it and the sinkhole has an estimated depth of about 100 feet

How much material is needed to fill the sinkhole?

Then , the material needed to fill the sinkhole will be dependent on the volume of the sinkhole.

Determine what information is needed to answer the question.

The information that is needed to answer this question are:

the base area of the sinkhole will be required; &

the height should also be known

if the base area is determined then we can proceed to determine how much material is needed to be calculated.

Do you think your estimate is more likely to be too high or too low

No, the estimate is not likely to be too high or too low rather the estimate of the material required will be almost equal to the volume of the sinkhole, but that does not implies that it will be exactly the same since the sinkhole is not uniform and regular in shape.

5 0

3 years ago

The mean hours of sleep that students get per night is 7 hours, the standard deviation of hours of sleep is 1.7 hours, and the d

densk [106]

Answer:

c. 3.6 and 10.4 hrs

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviations of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean 7, standard deviation 1.7.

For about 95% of students, nightly amount of sleep is between

7 - 2*1.7 = 7 - 3.4 = 3.6 hours

7 + 2*1.7 = 7 + 3.4 = 10.4 hours

So the correct answer is:

c. 3.6 and 10.4 hrs

5 0

3 years ago

A number is 6 greater than 1\2 another number. If the sum of the numbers is 21,find the numbers.

Lemur [1.5K]

Let 1 number equal x
Let the other number equal 1/2x + 6

x + (1/2x + 6) =21
1 & 1/2 x + 6 =21
1 & 1/2 x =15

5 0

3 years ago