Answer:
c.
Step-by-step explanation:
×
Answer:
Sonia practices for 96 mins (1 hour 36mins ) 0.8 = 80%
Step-by-step explanation:
Answer:
15;9;-8
Step-by-step explanation:
1. 5/3x-3=2/3x+12
x=15 once you combine like terms
2. 5x+35-3x+12=7x+2
2x+47=7x+2
5x=45
x=9
3. 12x+20-3=9x-7
12x+17=9x-7
3x=-24
x=-8
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>