Answer:
Step-by-step explanation:
Since the population standard deviation , is known, we use the z confidence interval for the mean.
This is given by:
For a 95% confidence interval we use .
It was also given that: ,
and
Let us substitute the values to get:
<u>Interpretation:</u>
We can say with 95% confidence that the interval between 1463.3 and 1580.7 SAT scores contains the population mean based on the sample 125 SAT scores.
Answer:
1. $35.075
2. 43.5 hours
3. 70%
4. Danny is correct
5. Abe's score out of the 30 points of the last quiz to get an overall checkup quiz grade of 80% should be 28.5
Step-by-step explanation:
The pay per hour for student tutors = $5.75
1. A tutor who worked 3.4 hours on Monday and 2.7 hours on Thursday has worked, 3.4 + 2.7 = 6.1 hours for the week, therefore
The week earning for the tutor = 6.1 × 5.75 = $35.075
2. The Club's tutoring budget per week = $250
The number of tutoring hours that can be provided per week is given by the relation;
3. The score of 21 out of 30 as a percentage is given as follows;
4. Where the second score is 45 out of a total of 60 points, we have;
Therefore, the increase in Abe's score is 5%, therefore, Danny is correct
5. To raise his checkup quiz grade to 80% overall, then we should have;
Where:
Q = The percentage grade of the last quiz
(145 + Q)×100 = 80×300 = 24000
145 + Q = 240
Q = 240 - 145 = 95%
Therefore, he has to score, 95% of 30 on the last quiz, which is thus;
Abe's score out of the 30 points of the last quiz to get an overall checkup quiz grade of 80% = 28.5 points.