Which of the following describes point C<br> (-2,1)<br> (-2,-1)<br> (1,-2)<br> (-1,-2)

In a class of 30 students there are 17 girls. two students are picked randomly to represent the class in the SRC. determine the

Alla [95]

Answer:

See below in bold,.

Step-by-step explanation:

There are 30-17 = 13 boys in the class.

a. Prob(First is a boy ) = 13/30 and Prob( second is a boy = 12/29).

As these 2 events are independent:

Prob( 2 boys being picked) = 13/30 * 12/29 = 26/145 or 0.179 to the nearest thousandth.

b. By a similar method to a:

Prob ( 2 girls being picked) = 17/30 * 16/29 = 136/435 = 0.313 to the nearest thousandth.

c. Prob (First student is a boy and second is a girl) = 13/30 * 17/29 = 221/870.

Prob ( first student is a girl and second is a boy) = 17/30 * 13/29 = 221/870

These 2 events are not independent so they are added:

Prob( one of the students is a boy) = 2 (221/870 = 221/435 = 0.508 to the nearest thousandth.

4 0

2 years ago

The travel time on a section of a Long Island Expressway (LIE) is normally distributed with a mean of 80 seconds and a standard

user100 [1]

Answer:

The travel time that separates the top 2.5% of the travel times from the rest is of 91.76 seconds.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 80 seconds and a standard deviation of 6 seconds.

This means that $\mu = 80, \sigma = 6$

What travel time separates the top 2.5% of the travel times from the rest?

This is the 100 - 2.5 = 97.5th percentile, which is X when Z has a p-value of 0.975, so X when Z = 1.96.

$Z = \frac{X - \mu}{\sigma}$

$1.96 = \frac{X - 80}{6}$

$X - 80 = 6*1.96$

$X = 91.76$

The travel time that separates the top 2.5% of the travel times from the rest is of 91.76 seconds.

3 0

2 years ago

You and your family left the house for a vacation at 8 A.M. You promptly fell asleep in the

poizon [28]

Answer:

201 miles.

Step-by-step explanation:

If you've traveled 124 miles in 2 hours, than in one hour must've been 62 miles. 62 multiplied by 3 is 186, which is how much miles have been traveled in 3 hours. Plus the 15 minutes would probably be 201 miles. Hope this helps!

8 0

3 years ago

Read 2 more answers

A ski lodge charges $26 per day for a pass and $1.50 for every ski lift ride. A second ski

malfutka [58]

Answer:

32=40

26=39

Step-by-step explanation:

8 0

2 years ago

Can someone help me please