If the speed limit on a highway is 70 miles per hour, about how fast is this in miles per minute?

We learned in that about 69.7% of 18-20 year olds consumed alcoholic beverages in 2008. We now consider a random sample of fifty

maw [93]

Answer:

(1) The expected number of people who would have consumed alcoholic beverages is 34.9.

(2) The standard deviation of people who would have consumed alcoholic beverages is 10.56.

(3) It is surprising that there were 45 or more people who have consumed alcoholic beverages.

Step-by-step explanation:

Let X = number of adults between 18 to 20 years consumed alcoholic beverages in 2008.

The probability of the random variable X is, p = 0.697.

A random sample of n = 50 adults in the age group 18 - 20 years is selected.

An adult, in the age group 18 - 20 years, consuming alcohol is independent of the others.

The random variable X follows a Binomial distribution with parameters n = 50 and p = 0.697.

The probability mass function of a Binomial random variable X is:

$P(X=x)={50\choose x}0.697^{x}(1-0.697)^{50-x};\ x=0,1,2,3...$

(1)

Compute the expected value of X as follows:

$E(X)=np\\=50\times 0.697\\=34.85\\\approx34.9$

Thus, the expected number of people who would have consumed alcoholic beverages is 34.9.

(2)

Compute the standard deviation of X as follows:

$SD(X)=\sqrt{np(1-p)}=\sqrt{50\times 0.697\times (1-0.697)}=10.55955\approx10.56$

Thus, the standard deviation of people who would have consumed alcoholic beverages is 10.56.

(3)

Compute the probability of X ≥ 45 as follows:

P (X ≥ 45) = P (X = 45) + P (X = 46) + ... + P (X = 50)

$=\sum\limits^{50}_{x=45} {50\choose x}0.697^{x}(1-0.697)^{50-x}\\=0.0005+0.0001+0.00002+0.000003+0+0\\=0.000623\\\approx0.0006$

The probability that 45 or more have consumed alcoholic beverages is 0.0006.

An unusual or surprising event is an event that has a very low probability of success, i.e. p < 0.05.

The probability of 45 or more have consumed alcoholic beverages is 0.0006. This probability value is very small.

Thus, it is surprising that there were 45 or more people who have consumed alcoholic beverages.

6 0

2 years ago

Now see if you can solve these word problems about time and distance.

ladessa [460]

Answer:

3.5 hours

Step-by-step explanation:

Ediburgh -------------------------------350 miles-------------------------London

Let the distance traveled by train from Edin to London be "x"

hence the distance traveled by train from London to Edin would be "350-x"

The rate of Edin to London train is 60
The rate of London to Edin train is 40

Let the time they meet be"t"

Now, we know distance formula to be D = RT

Where

D is distance

R is rate

and

T is time

Train from Edin to London:

x = 60t

Train from London to Edin:

350-x = 40t

Solving for x:

350 - 40t = x

We put this into first equation:

x = 60t

350 - 40t = 60t

350 = 100t

t = 350/100

t = 3.5

They meet after 3.5 hours

4 0

3 years ago

y = -16x2 + 32x - 10 This parabola has x-intercepts, representing the times when the dolphin's height above water is feet.

Lina20 [59]

Answer: This parabola has 0.3875 x-intercepts,
representing the times when the dolphin's height above water is 
0 feet.

The x-intercept is the point where the graph crosses the x-axis, which is when the value is y=0.
The calculation for y=0 would be
Y = -16x2 + 32x - 10
0 = -16x2 + 32x - 10
-8x2 + 16x - 5=0

-b +-√(b^2-4ac) /2a=
-16 +-√(16^2-4(-8)(-5)) /2(-8) =
-16+- √(256-160/ -16 =
-16+- √(96/ -16 =
-16+- 9.8/ -16 =
x1= 0.3875
x2= -1.6125

6 0

3 years ago

Read 2 more answers

A pole that is 3.4 m tall casts a shadow that is 1.54 m long. At the same time, a nearby building casts a shadow that is 35.75 m

inna [77]

Answer:

The building would be 78.92 meters tall.

Step-by-step explanation:

If the shodow of a 3.4m tall pole is 1.54m tall, and you have the shadow's height, then you make a cross, multiply-divide ratio table.

5 0

2 years ago

Determine 6th term in the geometric sequence whose first term is 3 and whose common ratio is -4.