330/11=30
300 like Drake
30 like Shawn Mendez
Answer:
50%
Step-by-step explanation:
Divide the amount sold by the total amount started out
63/126 = .5
multiply by 100 to get into percent form
Answer:
89–100
Step-by-step explanation:
Let x represent the grade on the fifth test. The average for 5 tests wants to be between 80 and 90, so we have ...
80 ≤ (78 +62 +91 +80 +x)/5 ≤ 90
Multiplying by 5 gives
400 ≤ 311 +x ≤ 450
Subtracting 311 gives the range for the fifth test grade.
89 ≤ x ≤ 139
Since the maximum available score is 100, the range on the 5th test for an overall B grade is ...
89 ≤ x ≤ 100 . . . . where x is the grade on the 5th test
The mean of the confidence interval is (0.3775 + 0.6225) / 2 = 0.5. Therefore, the standard deviation of the proportion would have been sqrt[0.5*(1 - 0.5) / n], where n is the sample size. This expression simplifies to sqrt(0.25/n).
A 95% CI has a corresponding z = 1.96, so since the distance from 0.5 to 0.3775 (or 0.6225 to 0.5) is equal to 0.1225. Therefore, if we divide 0.1225 / 1.96 = 0.0625, we get the value of the SD, and this should be equal to sqrt(0.25/n).
0.0625 = sqrt(0.25/n)
n = 64
This means that the proportion was 0.5 and the sample size was 64.
