Answer:
They can either decrease the confidence level or increase the sample size, that is, survey more students.
Step-by-step explanation:
The width of a confidence interval is given by:

In which z is the critical value correponding to the confidence level(higher confidence level, higher z is),
is the standard deviation of the population and n is the size of the sample.
The students realize that this interval contains a large margin of error. What can they do to make a narrower interval?
Looking at the formula for M, they can either decrease the confidence level or increase the sample size, that is, survey more students.
Step-by-step explanation:
3x=-13+1
3x = - 12
x = -12/3
x= -4
Answer:
Option D -17.5 degrees is correct answer
Step-by-step explanation:
Since a calendar week has 7 days. and temperature is falling by -2.5 daily.
So, On Day 1 Temperature is -2.5 degrees
On Day 2 Temperature is -2.5 + -2.5 = -5 degrees
On Day 3 Temperature is = -5 + -2.5 = -7.5 degrees
On Day 4 Temperature is = -7.5 + -2.5 = -10 degrees
On Day 5 Temperature is = -10 + -2.5 = -12.5 degrees
On Day 6 Temperature is = -12.5 + -2.5 = -15 degrees
On Day 7 Temperature is = -15 + -2.5 = -17.5 degrees
So, Option D -17.5 degrees is correct answer.
Answer: x=7.7, y=40
3/x = 15/38.5
38.5*3=115.5
115.5/15= 7.7
x=7.7
3/8 = 15/y
15*8=120
120/3= 40
y=40
orrrr you can just easily find the scale factor which is 5, multiply 8 by 5 and get 40. And 38.5/5 which is 7.7
Answer:

note that -11 itself is not included. the circle is empty, not filled