Answer: 2/7
Step-by-step explanation: if there are 7 cards and two of them are purple, we can show this as 2/7
Answer: 19 years
Step-by-step explanation:
Given
Amount invested 
Rate of interest 
after 1-year amount becomes

After n years it is

Sum accumulated is 

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>
It should be d. , Because if you take the equation 3x+y=9, and make it slope intercept form, it would be y= -3x+9. -3 is the slope, and 9 is the y intercept. D is the answer.
Answer:
4.8
Step-by-step explanation:
Um, I'm not sure how to explain, but watch a khan academy video on it