Answer:
Hi!
Step-by-step explanation:
What I do when I fail or didn't study and get a bad grade is explain this to your teacher and next time study. Take notes!
3x=x+3 2x=3 x=3/2
Move x terms to one side, then solve
Answer:
x+14
Step-by-step explanation:
(12+x)+2
12+x+2
x+(12+2)
x+14
let's say the breakfast price was "x", so that's the 100%, and we know she gave 20% of that and that is 1.80.
so, 1.80 is 20%, and "x" is the 100%, what is "x"?
Answer: a) margin of error = 61.25, b) sample size when margin of error is 45 = 30
Step-by-step explanation:
The formulae to get the margin of error of a confidence interval is given as
Margin of error = critical value * (σ/√n)
Where σ = population standard deviation = 125
n = sample size = 16
Critical value =Zα/2 = 1.96 ( this is so because we are performing a 95% confidence level test then level of significance (α) will be 5% and since our test is of two values, it will be 2 tailed).
Margin of error = 1.96 * (125/√16)
Margin of error = 1.96 * 125/4
Margin of error = 1.96 * 31.25
Margin of error = 61.25
Question b)
Margin of error = 45
Critical value =Zα/2 = 1.96
Population standard deviation = σ = 125
Sample size =n =??
By recalling the formulae
Margin of error = critical value * (σ/√n)
45 = 1.96 * (125/√n)
45 = (1.96 * 125)/√n
45 = 245/√n
45 * √n = 245
√n = 245/ 45
√n = 5.444
n = (5.444)²
n= 29.64 which is approximately 30.
