Answer:
P = 0.008908
Step-by-step explanation:
The complete question is:
The table below describes the smoking habits of a group of asthma sufferers
Nonsmokers Light Smoker Heavy smoker Total
Men 303 35 37 375
Women 413 31 45 489
Total 716 66 82 864
If two different people are randomly selected from the 864 subjects, find the probability that they are both heavy smokers.
The number of ways in which we can select x subjects from a group of n subject is given by the combination and it is calculated as:
Now, there are 82C2 ways to select subjects that are both heavy smokers. Because we are going to select 2 subjects from a group of 82 heavy smokers. So, it is calculated as:
At the same way, there are 864C2 ways to select 2 different people from the 864 subjects. It is equal to:
Then, the probability P that two different people from the 864 subjects are both heavy smokers is:
Answer:
+120/169 or -120/169
Step-by-step explanation:
- let
![cos^{-1}[\frac{5}{13} ] = \alpha](https://tex.z-dn.net/?f=cos%5E%7B-1%7D%5B%5Cfrac%7B5%7D%7B13%7D%20%20%5D%20%3D%20%5Calpha)
where, alpha is some angle that satisfies the assumed condition.
- so,
[ taking cos to the other side or applying cos on both sides]
- now, substitute this in the given expression
as sin
= 
[by general trigonometry formula: ![cos^{2}[\beta] +sin^{2}[\beta]=1](https://tex.z-dn.net/?f=cos%5E%7B2%7D%5B%5Cbeta%5D%20%20%2Bsin%5E%7B2%7D%5B%5Cbeta%5D%3D1)
]
so if , we can get sin
from the above formula as + or - 12/13
(because, after taking square root on both sides we keep + or -]
- as, sin
![2\beta = 2*sin[\beta ]*cos[\beta ]](https://tex.z-dn.net/?f=2%5Cbeta%20%20%3D%202%2Asin%5B%5Cbeta%20%5D%2Acos%5B%5Cbeta%20%5D)
[by general trigonometry formula]
- here, now
![sin[2\alpha ]=2*(+or- 12/13)*5/13\\](https://tex.z-dn.net/?f=sin%5B2%5Calpha%20%5D%3D2%2A%28%2Bor-%2012%2F13%29%2A5%2F13%5C%5C)
so, the final value can be 120/169 or -120/169.
Answer:
-3/4x
Step-by-step explanation:
down 3 left 4 rise/run
You should use a T distribution to find the critical T value based on the level of confidence. The confidence level is often given to you directly. If not, then look for the significance level alpha and compute C = 1-alpha to get the confidence level. For instance, alpha = 0.05 means C = 1-0.05 = 0.95 = 95% confidence
Use either a table or a calculator to find the critical T value. When you find the critical value, assign it to the variable t.
Next, you'll compute the differences of each pair of values. Form a new column to keep everything organized. Sum everything in this new column to get the sum of the differences, which then you'll divide that by the sample size n to get the mean of the differences. Call this dbar (combination of d and xbar)
After that, you'll need the standard deviation of the differences. I recommend using a calculator to quickly find this. A spreadsheet program is also handy as well. Let sd be the standard deviation of the differences
The confidence interval is in the form (L, U)
L = lower bound
L = dbar - t*sd/sqrt(n)
U = upper bound
U = dbar + t*sd/sqrt(n)
Answer:
If your investment dropped 7% and then increased by 8% you will not be a percent ahead. The reason being is that the increase is a lower amount and the decrease was on a larger amount.
For example, if you have $100 invested. 100*.07=$7, 100-7=$93 remaining. 93*08= $7.44. 93+7.44=100.44 (a .44 increase from the original number). One percent increase from the original number would have $101.
