Answer: 
Step-by-step explanation:
- A null hypothesis is a hypothesis where a researcher generally try to disprove, it says that there is no statistically significant relationship between the two variables .
- An alternative hypothesis says that there is a statistical significance between two variables.
Claim 1. : Mean age of online dating service users is 40 years.
i.e. 
, since it has equals sign so we take this as null hypothesis.
Claim 2. : Mean age of online dating service users is not 40 years.
⇒ Null Hypothesis :
Alternative hypothesis :
Answer:
$1.30
Step-by-step explanation:
Let x = the cost of the pencil
Let x + .80 = the cost of the pen
Let 4(x + .80) = the cost of the binder
x + x + .80 + 4(x + .80) = 11.80
2x + .80 + 4x + 3.20 = 11.80
6x + 4.00 = 11.80
6x = 7.80
x = $1.30
x + .80 = $2.10
4(x + .80) = $8.40
Assuming this is a binomial distribution, P(x=15) = 0.0416
Answer:
C, 33 1/3%
Step-by-step explanation:
Because there are only two even number that follow this rule: 2<x≥6, and since there are only 6 possible outcomes, the probabilty is 2/6, which is 1/3. In a percent form, this is 100%*2/3, or 33 1/3%.
