Please I needa answer !!

Can someone answer my last two questions?

MAVERICK [17]

Answer:

Hit me with them

Step-by-step explanation:

6 0

3 years ago

1.44 Make-up exam: In a class of 28 students, 27 of them took an exam in class and 1 student took a make-up exam the following d

Olenka [21]

Answer:

a) Decrease

b) New mean = 78.43

c) Decrease

Step-by-step explanation:

We are given the following in the question:

Total number of students in class = 28

Average of 27 students = 79

Standard Deviation of 27 students = 6.5

New student's score = 63

a) The new student's score will decrease the average.

b) New mean

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

$Mean = \dfrac{\displaystyle\sum x_i}{27} = 79\\\\\sum x_i = 27\times 79 = 2133$

New mean =

$\text{ New mean} =\dfrac{ \displaystyle\sum x_i +63}{28}\\\\ =\dfrac{2133+63}{28}= \dfrac{2196}{28} = 78.43$

Thus, the new mean is 78.43

c) Since the new mean decreases, standard deviation for new scores will decrease.

This is because the new value is within the usual values i.e. within two standard deviations of the mean. So, this wont cause a lot of variation as this value will be closer to already available data values. Also number of observations (n) in the denominator is increasing. Based on both these points we can conclude that standard deviation will decrease

Formula for Standard Deviation:

$\text{Standard Deviation} = \sqrt{\displaystyle\frac{\sum (x_i -\bar{x})^2}{n}}$

where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

7 0

3 years ago

The ground temperature at an airport is 10 °C. The temperature decreases by 5.4 °C for every increase of 1 kilometer above the g

Paraphin [41]

The temperature outside a plane flying at an altitude of 5 kilometers is -17°C.

Given that,

The ground temperature at the airport is 10 °C.
The decrease in temperature is 5.4°C for each & every rise in 1 kilometer.

Based on the above information, the temperature outside should be

The decrease in the temperature should be

= 5.4×5

= 27°C

Now the final temperature is

= 10 - 27

= -17°C

Therefore we can conclude that the temperature outside a plane flying at an altitude of 5 kilometers is -17°C.

Learn more: brainly.com/question/20459283

5 0

3 years ago

Suponhamos que temos x casos confirmados de coronavírus e y casos suspeitos. A - Se triplicar os casos confirmados e cair a meta

aleksandr82 [10.1K]

Answer:

[3x + (y/2)]

Step-by-step explanation:

English Translation

Suppose we have x confirmed cases of coronavirus and y suspected cases. A - If the confirmed cases triple and half of the suspects fall, we will have the following expression to represent the total number of cases:

Solution

Number of confirmed cases = x

Number of suspected cases = y

Number of confirmed cases triples and becomes 3x

Half of the suspected cases fall and becomes (y/2)

Total number of cases then becomes

[3x + (y/2)]

In Portugese/Em português

Número de casos confirmados = x

Número de casos suspeitos = y

O número de casos confirmados triplica e se torna 3x

Metade dos casos suspeitos cai e se torna (y / 2)

O número total de casos passa a ser

[3x + (y / 2)]

Hope this Helps!!!

Espero que isto ajude!!!

8 0

3 years ago

A box of jerseys for a pick-up game of basketball contains 9 extra-large jerseys, 6 large jerseys, and 5 medium jerseys. If you

aleksley [76]

Answer:

1/114 or 0.008772

Step-by-step explanation:

I am not very sure, my answer seems unlikely, but here's what I think:

There are 20 jerseys in the box to begin with, and 5 medium jerseys that you can have.

Therefore, the probability of you randomly grabbing a medium sized jersey is 5/20 or 1/4.

After taking out one medium sized jersey, there are 19 jerseys in the box and 4 medium jerseys you can pick from.

The probability of you randomly grabbing a medium sized jersey is 4/19.

After taking out another medium sized jersey, there are 18 jerseys left in the box and 3 medium jerseys you can pick from.

The probability of you randomly grabbing a medium sized jersey is 3/18.

To get the answer, you do 1/4 * 4/19 * 3/18, and get 1/114, or 0.00877192982.

If you round that to the nearest millionth, it's 0.008772

Don't judge me, it might not be correct.

4 0

3 years ago