What is 3 1/3 (-2 1/4) 1 5/6=?

Subjects for the next presidential election poll are contacted using telephone numbers in which the last four digits are randoml

sammy [17]

Answer:

probability at least one zero is 0.3439

Step-by-step explanation:

given data

last four digits = randomly selected

to find out

probability that for one such phone number the last four digits include at least one 0.

solution

we know there are total 10 digit

so we first find probability of non zero digit i.e.

Probability ( non zero ) = 9 /10 = 0.9

and now we find probability of none of digit zero only event happen n= 4 time in a row by multiplication rules i.e

Probability ( none zero in 4 digit ) = $0.9^{n}$

Probability ( none zero in 4 digit ) = $0.9^{4}$

Probability ( none zero in 4 digit ) = 0.6561

so we can say probability at least one zero = 1 - Probability ( none zero in 4 digit )

probability at least one zero = 1 - 0.6561

probability at least one zero is 0.3439

3 0

3 years ago

A geology teacher takes her class on an annual field trip to analyze rock samples. They use randomized sets of

Tpy6a [65]

Second option would be the answer

8 0

3 years ago

Read 2 more answers

One number exceeds another by 5. The sum of the numbers is 25. What are the numbers?

Maurinko [17]

The numbers are ten and fifteen (brainliest please)

5 0

2 years ago

Read 2 more answers

I need help with number 3

Juli2301 [7.4K]

Answer:

a) 8 apples

b) 5 oranges

c) 2 oranges and 6 apples

Step-by-step explanation:

a) 8 apples × 1$ = 8$ < 10$

b) 5 oranges × 2$ = 10$

c) 2 oranges × 2$ = 4$

6 apples × 1$ = 6$ (4+6=10)

7 0

3 years ago

Read 2 more answers

A marketing firm is considering making up to three new hires. Given its specific needs, the management feels that there is a 50%

IRISSAK [1]

Answer:

a) 0.9

b) Mean = 1.58

Standard Deviation = 0.89

Step-by-step explanation:

We are given the following in the question:

A marketing firm is considering making up to three new hires.

Let X be the variable describing the number of hiring in the company.

Thus, x can take values 0,1 ,2 and 3.

$P(x\geq 2) = 50\%= 0.5\\P(x = 0) = 10\% = 0.1\\P(x = 3) = 18\% = 0.18$

a) P(firm will make at least one hire)

$P(x\geq 2) = P(x=2) + P(x=3)\\0.5 = P(x=2) + 0.18\\ P(x=2) = 0.32$

Also,

$P(x= 0) +P(x= 1) + P(x= 2) + P(x= 3) = 1\\ 0.1 + P(x= 1) + 0.32 + 0.18 = 1\\ P(x= 1) = 1- (0.1+0.32+0.18) = 0.4$

$\text{P(firm will make at least one hire)}\\= P(x\geq 1)\\=P(x=1) + P(x=2) + P(x=3)\\ = 0.4 + 0.32 + 0.18 = 0.9$

b) expected value and the standard deviation of the number of hires.

$E(X) = \displaystyle\sum x_iP(x_i)\\=0(0.1) + 1(0.4) + 2(0.32)+3(0.18) = 1.58$

$E(x^2) = \displaystyle\sum x_i^2P(x_i)\\=0(0.1) + 1(0.4) + 4(0.32) +9(0.18) = 3.3\\V(x) = E(x^2)-[E(x)]^2 = 3.3-(1.58)^2 = 0.80\\\text{Standard Deviation} = \sqrt{V(x)} = \sqrt{0.8036} = 0.89$

7 0

3 years ago