Fun. I prefer Oxymetazoline.
For the control group we have a headache probability of
c = 368/1671 = .220
For the experimental group we have a headache probability of
e = 494/2013 = .245
The observed difference is
d = e - c = .025
The variance of the difference is
s² = c(1-c)/n₁ + e(1-e)/n₂
so the standard deviation is

We get a t statistic on the difference of
t = d/s = .025/.0139 = 1.79
We're interested in the one sided test, P(d > 0). We have enough dfs to assume normality. We look up in the standard normal table
P(z < 1.79) = .96327
so
p = P(z > 1.79) = 1 - .96327 = 0.037 = 3.7%
Answer: That's less that 10% so we have evidence to conclude that headaches are significantly greater in the experimental group.
All you have to do is multiply your number and then add them together !!
(x-8)^2+y^2=225 I'm not able to factor it
Answer:
6 5/8
Step-by-step explanation:
You need to add 2 3/4 and 3 7/8
2 3/4 as an improper fraction is 11/4 and 3 7/8 as an improper fraction 31/8
To add them you need to have common denominators
So you multiply 11/4 by 2/2 which is 22/8
Now you can add them
22/8+31/8 = 53/8
53/8 = 6 5/8