Answer:
The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
Answer:
x=6.09cm
Step-by-step explanation:
Working out AB:
7.5²+4.9²
= √80.26
AB= 8.96cm
To work out x:
AB is the opposite, where BC is the adjacent. This means that we have to use TOA.
x=8.96/Tan(55.8)
x= 6.09cm
Step-by-step explanation:
a^2 + b^2 = c^2
(x+2)^2 + 4x^2 = (3x+4)^2
(x+2)(x+2)+ 4x^2= (3x+4)(3x+4)
x^2 + 2x + 2x + 4 + 4x^2 = 9x^2 + 12x + 12 x + 16
5x^2 + 4x + 4 = 9x^2 + 24x + 16
-4x^2 - 20x - 12 = 0
now we can use the quadratic formula
(-b±√(b²-4ac))/(2a)
I can't type all this so
.....
x = -0.697224362 or -4.302775638
AB can't be negative so it's the first one
so it's equals to 1.302775638
Answer:-
x=-5/2
Step-by-step explanation:
x+2/3=-1/6
after cross-mutiplying,
6(x+2)=-3
6x+12=-3
6x=-3-12
6x=-15
x=-15/6
x=-5/2
hope this helps u!!
