What is the value of the expression 3/3^-2 ?

Stefanie spends entire allowance one month she spends 1/2 of a on new clothes 1/4 on food 1/6 on movies and 1/12 on Music how mu

Komok [63]

Answer:

Option D: 1/3

Step-by-step explanation:

Let

x ------> the entire Stefanie's allowance

we know that

She spends on clothes (1/2)x

She spends on movies (1/6)x

To find out how much more does she spend on clothes that he does on movies, subtract the amount she spends on movies from the amount she spend on clothes

$\frac{1}{2}x-\frac{1}{6}x=\frac{2}{6}x$

Simplify

$\frac{1}{3}x$

therefore

She spends 1/3 more on clothes that he does on movies

4 0

3 years ago

Software filters rely heavily on ""blacklists"" (lists of known ""phishing"" URLs) to detect fraudulent e-mails. But such filter

crimeas [40]

Answer:

a) $X \sim Binom(n=16, p=0.2)$

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:

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

The expected value is given by this formula:

$E(X) = np=16*0.2=3.2$

b) $P(X=0)=(16C0)(0.2)^{0} (1-0.2)^{16-0}=0.02815$

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".

Part a

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

$X \sim Binom(n=16, p=0.2)$

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:

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

The expected value is given by this formula:

$E(X) = np=16*0.2=3.2$

Part b

For this case we want this probability:

$P(X=0)$