Answer:
Sample size should be atleast 617
Step-by-step explanation:
given that a 95% confidence interval for the mean of a population is to be constructed and must be accurate to within 0.3 unit.
i.e. margin of error <0.3
Std devition sample = 3.8
For 95% assuming sample size large we can use z critical value
Z critical = 1.96
we have

Sample size should be atleast 617 to get an accurate margin of error 0.3
First graph is the correct one.
when x= 1
y=f(x) = -√1 = -1
when x= 2
y= -√2
Answer: 1/7
Step-by-step explanation:
Total questions answered = 49
Harry correct answers = 42
Harry wrong answers = (49 - 42) = 7
Thus, the only fraction of wrong answers = (Number of wrong answers / Total number of questions answered)
i.e 7/49
= 1/7
Thus, harry answered 1/7 of the 49 questions wrongly.
Answer:
7
Step-by-step explanation:
Let 'x' represent the number of tickets that Teresa sold, and x is integer and x>=0 (you can not sell negative number of tickets)
6 + 2x < 22
x < 8
The range of possible number of tickets that Teresa sold is {0, 1, 2, 3, 4, 5, 6, 7}.