Help? ill mark brainlest

Which of the following number sentences is true? A -9=9 B-9=-(9) C 9=(-9) D 9=-(-9)

kondaur [170]

Answer:

A and D are the true number sentences

3 0

2 years ago

A man on the fifth floor of a building shouts down to a person on the street. If the angle of elevation from the street to the m

AleksandrR [38]

Answer: 57 ft

Step-by-step explanation: Because drawing it up, we can make a right angled triangle with the right angle between the height of the man in the building and the distance out from the building of the man in the street, and the 35 degrees between the line connecting the man in the street with the man in the building, and the line out from the building of the man in the street. Then, tan of the 35 degree angle is = to opposite (40ft)/adjacent (to solve for). By cross multiplication, the A or adjacent (dist out from the building) = 40/0.7 (0.7 = tan of 35 degrees) so the answer is 57 ft.

3 0

2 years ago

Read 2 more answers

Plzzz help me Asap I will give you brainliest. I promise

kari74 [83]

He need to earn 48
Inequality : 80-32=x

8 0

2 years ago

Psychologist Michael Cunningham conducted a survey of university women to see whether, upon graduation, they would prefer to mar

bagirrra123 [75]

Answer:

A.The probability that exactly six of Nate's dates are women who prefer surgeons is 0.183.

B. The probability that at least 10 of Nate's dates are women who prefer surgeons is 0.0713.

C. The expected value of X is 6.75, and the standard deviation of X is 2.17.

Step-by-step explanation:

The appropiate distribution to us in this model is the binomial distribution, as there is a sample size of n=25 "trials" with probability p=0.25 of success.

With these parameters, the probability that exactly k dates are women who prefer surgeons can be calculated as:

$P(x=k) = \dbinom{n}{k} p^{k}(1-p)^{n-k}\\\\\\P(x=k) = \dbinom{25}{k} 0.25^{k} 0.75^{25-k}\\\\\\$

A. P(x=6)

$P(x=6) = \dbinom{25}{6} p^{6}(1-p)^{19}=177100*0.00024*0.00423=0.183\\\\\\$

B. P(x≥10)

$P(x\geq10)=1-P(x$

$P(x=0) = \dbinom{25}{0} p^{0}(1-p)^{25}=1*1*0.0008=0.0008\\\\\\P(x=1) = \dbinom{25}{1} p^{1}(1-p)^{24}=25*0.25*0.001=0.0063\\\\\\P(x=2) = \dbinom{25}{2} p^{2}(1-p)^{23}=300*0.0625*0.0013=0.0251\\\\\\P(x=3) = \dbinom{25}{3} p^{3}(1-p)^{22}=2300*0.0156*0.0018=0.0641\\\\\\P(x=4) = \dbinom{25}{4} p^{4}(1-p)^{21}=12650*0.0039*0.0024=0.1175\\\\\\P(x=5) = \dbinom{25}{5} p^{5}(1-p)^{20}=53130*0.001*0.0032=0.1645\\\\\\P(x=6) = \dbinom{25}{6} p^{6}(1-p)^{19}=177100*0.0002*0.0042=0.1828\\\\\\$

$P(x=7) = \dbinom{25}{7} p^{7}(1-p)^{18}=480700*0.000061*0.005638=0.1654\\\\\\P(x=8) = \dbinom{25}{8} p^{8}(1-p)^{17}=1081575*0.000015*0.007517=0.1241\\\\\\P(x=9) = \dbinom{25}{9} p^{9}(1-p)^{16}=2042975*0.000004*0.010023=0.0781\\\\\\$

$P(x\geq10)=1-(0.0008+0.0063+0.0251+0.0641+0.1175+0.1645+0.1828+0.1654+0.1241+0.0781)\\\\P(x\geq10)=1-0.9287=0.0713$

C. The expected value (mean) and standard deviation of this binomial distribution can be calculated as:

$E(x)=\mu=n\cdot p=25\cdot 0.25=6.25\\\\\sigma=\sqrt{np(1-p)}=\sqrt{25\cdot 0.25\cdot 0.75}=\sqrt{4.69}\approx2.17$

4 0

2 years ago

FIND THE THIRD,FIFTH AND TENTH TERM SEQUENCE DESCRIBED BY EACH RULE

Karolina [17]

In order to solve for a nth term in an arithmetic sequence, we use the formula written as:

an = a1 + (n-1)d

where an is the nth term, a1 is the first value in the sequence, n is the term position and d is the common difference.

THIRD
A3=4+(3-1)(-5)
A3 = -6

A(3)=-2(3-1)(-5)
A3 = 20

FIFTH
A5=4+(5-1)(-5)
A5 = -16

A(5)=-2(5-1)(-5)
A5 = 40

TENTH
A10=4+(10-1)(-5)
A10 = -41

A(10)=-2(10-1)(-5)
A10 = 90

8 0

3 years ago