C. 75
70+35+x=180
70+35=105
180-105=75
Answer:
B. 10/91
Step-by-step explanation:
Box has 5 red buttons and 9 blue buttons.
We add 5 and 9 to get the total buttons.
5 + 9 = 14
Then, we find the probability for a red button.
5/14 = .35
Now, that we've taken out 1 button.
The amount of buttons available changes.
14 - 1 = 13
There are 4 red buttons remaining.
The probability for a red button changes to 4/13.
4/13 = .30
Then, we multiply both probabilities.
.30 x .35 = .111
Convert to a fraction.
.111 = 10/91
Thus it would be B.
I say it’s c it makes the most sense to me
Step-by-step explanation:
13.8564064606
hope it helps
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>