Answer:
60 students
Step-by-step explanation:
The confidence interval of a proportion is given by:
![p\pm z*\sqrt{\frac{p*(1-p)}{n} }](https://tex.z-dn.net/?f=p%5Cpm%20z%2A%5Csqrt%7B%5Cfrac%7Bp%2A%281-p%29%7D%7Bn%7D%20%7D)
Where 'p' is the proportion of students who responded 'yes', 'z' is the z-score for a 95% confidence interval (which is known to be 1.960), and 'n' is the number of students in the sample.
If the confidence interval is from 0.584 to 0.816, then:
![p=\frac{0.584+0.816}{2}=0.7 \\0.816-0.584=2*(1.96*\sqrt{\frac{p*(1-p)}{n}}) \\0.116=1.96*\sqrt{\frac{0.7*(1-0.7)}{n}}\\n=16.8966^2*(0.7*0.3)\\n=60\ students](https://tex.z-dn.net/?f=p%3D%5Cfrac%7B0.584%2B0.816%7D%7B2%7D%3D0.7%20%5C%5C0.816-0.584%3D2%2A%281.96%2A%5Csqrt%7B%5Cfrac%7Bp%2A%281-p%29%7D%7Bn%7D%7D%29%20%5C%5C0.116%3D1.96%2A%5Csqrt%7B%5Cfrac%7B0.7%2A%281-0.7%29%7D%7Bn%7D%7D%5C%5Cn%3D16.8966%5E2%2A%280.7%2A0.3%29%5C%5Cn%3D60%5C%20students)
60 students were in the sample.
Answer:
-x^2 - 11x -30
Step-by-step explanation:
Solve using foiling. Ignore the -1 to begin with and just look at the part in parenthesis. Do x from the first parenthesis times the stuff in the second parenthesis.
ie: x(x) and x(6)
ie: x^2 + 6x
Then do the 5 times the things in the second parenthesis.
ie: 5(x) and 5(6)
ie: 5x + 30
Then add what you got from multiplying the first value to what you got from multiplying the second.
ie: x^2 + 11x + 30
This is a trinomial because it has three different variables. Now change all the signs to negative because of the -1 out front.
ie: -x^2 - 11x -30
I'm certain there isn't a number that satisfies your conditions.
There's one multiple of 69 between 55 and 101: 69
And two multiples of 18 between 55 and 101: 72 and 90.