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2 years ago

Help please!!!!! ASAPPPP

Mathematics

1 answer:

r-ruslan [8.4K]2 years ago

5 0

Answer:

the numerator is 31 and the bottom is 8

Step-by-step explanation:

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6 = 2(1+2) =<br> Somebody help me answer this please

Kitty [74]

Answer:

Step-by-step explanation:

6 = 2(1+2)

Use distributive property (Multiply 2 and 1. Then multiply 2 and 2)

6 = 2+4

Now add

6=6

This means the statement is true

3 0

2 years ago

Read 2 more answers

How do I do this a second way? I totally forgot because I haven't done it in so long.

ira [324]

You take away the 4 from the 8 which is equal to 4 then you have to barrow from the 2 to make the 4 to 14 and when you wait you are basically right your calculation is right

5 0

3 years ago

In a particular faculty 60% of students are men and 40% are women. In a random sample of 50 students what is the probability tha

zimovet [89]

Answer:

a) The expected value is given by:

$E(X) = np = 50*0.4 = 20$

and the variance is given by:

$Var(X) =np(1-p) = 50*0.4*(1-0.4) = 12$

b) $P(X>25)= 1-P(X\leq 25)$

And we can find this probability with the following Excel code:

=1-BINOM.DIST(25,50,0.4,TRUE)

And we got:

$P(X>25)= 1-P(X\leq 25)=0.0573$

c) 1) Random sample (assumed)

2) np= 50*0.4= 20 >10

n(1-p) =50*0.6= 30>10

3) Independence (assumed)

Since the 3 conditions are satisfied we can use the normal approximation:

$X \sim N(\mu = 20 , \sigma= 3.464)$

d) $P(X>25) = 1-P(Z< \frac{25-20}{3.464}) = 1-P(z$

e) $P(X>25)= P(X>25.5) = 1-P(X \leq 25.5)$

$P(X>25)= P(X>25.5) = 1-P(X \leq 25.5)= 1-P(Z$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=50, p=0.4)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

Part a

The expected value is given by:

$E(X) = np = 50*0.4 = 20$

and the variance is given by:

$Var(X) =np(1-p) = 50*0.4*(1-0.4) = 12$

Part b

For this case we want to find this probability:

$P(X>25)= 1-P(X\leq 25)$

And we can find this probability with the following Excel code:

=1-BINOM.DIST(25,50,0.4,TRUE)

And we got:

$P(X>25)= 1-P(X\leq 25)=0.0573$

Part c

1) Random sample (assumed)

2) np= 50*0.4= 20 >10

n(1-p) =50*0.6= 30>10

3) Independence (assumed)

Since the 3 conditions are satisfied we can use the normal approximation:

$X \sim N(\mu = 20 , \sigma= 3.464)$

Part d

We want this probability:

$P(X>25) = 1-P(Z< \frac{25-20}{3.464}) = 1-P(z$

Part e

For this case we use the continuity correction and we have this:

$P(X>25)= P(X>25.5) = 1-P(X \leq 25.5)$

$P(X>25)= P(X>25.5) = 1-P(X \leq 25.5)= 1-P(Z$

4 0

3 years ago

PLEASE HELP?

Darya [45]

Answer:

1/3

Step-by-step explanation:

The number of people over 40 is 20 + 30 + 35 = 85.

So the probability is 85/255, which reduces to 1/3.

8 0

3 years ago

If you going to answer one question say it in the comments it's gonna be the waste of time bc the answer is going to be deleted

oksano4ka [1.4K]

I am going to do number 2 so when you subtract decimals you have to add two zeros like this 10.00 or 0.25 so now when you subtract you get $9.75

6 0

3 years ago