Answer:
Step-by-step explanation:
The mean SAT score is
, we are going to call it \mu since it's the "true" mean
The standard deviation (we are going to call it
) is

Next they draw a random sample of n=70 students, and they got a mean score (denoted by
) of 
The test then boils down to the question if the score of 613 obtained by the students in the sample is statistically bigger that the "true" mean of 600.
- So the Null Hypothesis 
- The alternative would be then the opposite 
The test statistic for this type of test takes the form

and this test statistic follows a normal distribution. This last part is quite important because it will tell us where to look for the critical value. The problem ask for a 0.05 significance level. Looking at the normal distribution table, the critical value that leaves .05% in the upper tail is 1.645.
With this we can then replace the values in the test statistic and compare it to the critical value of 1.645.

<h3>since 2.266>1.645 we can reject the null hypothesis.</h3>
Answer: 9, 1/20, 9/20
Step-by-step explanation:
1) 9 pieces
2) Size of each pieces:

3) Area of the shaded rectangle:

Answer:
7 cards.
Step-by-step explanation:
60-39.5=20.5, that's what he has left if he buys 5 cards.
so, if you buy 2 more cards, that would be 18 dollars so 20.5-18=2.5
5 cards+ 2 cards= 7 cards.
He still hzs 2.5 dollars left
The value of x is 243
(correct me if wrong)