Answer:
3x=21
X=7
Step-by-step explanation:
Answer:
6+18 pls give brainlest
Step-by-step explanation:
How to solve your problem
3(2+6)
Simplify
1
Distribute
3(2+6)
6+18
Solution
6+18
Answer:
A sample of 1068 is needed.
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
.
The margin of error is:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?
We need a sample of n.
n is found when M = 0.03.
We have no prior estimate of
, so we use the worst case scenario, which is 
Then






Rounding up
A sample of 1068 is needed.
Answer:
table:
.1, .25, .35, .2, .1
p(x=4) = .1
p(x<2) = .35
p(3≤x≤4)= .55
1.95, 1.12
Step-by-step explanation:
this is kind of hard to read, but i think i've got it
mean:
0*.1+1*.25+2*.35+3*.2+4*.1= 1.95
The second moment:
0²*.1+1²*.25+2²*.35+3²*.2+4²*.1= 5.05
the variance is the second moment minus the first moment squared (first moment is the mean) and then the standard deviation is the square root of the mean
5.05-1.95²= 1.2475 √1.2475= 1.1169 or 1.12