Answer:
x=-2
Step-by-step explanation:
add 18 to both sides, simplify, add 6x to both sides, simplify, divide both sides by -12.then simplify again... I hope that helps...
Answer:
c) Is not a property (hence (d) is not either)
Step-by-step explanation:
Remember that the chi square distribution with k degrees of freedom has this formula

Where N₁ , N₂m ....
are independent random variables with standard normal distribution. Since it is a sum of squares, then the chi square distribution cant take negative values, thus (c) is not true as property. Therefore, (d) cant be true either.
Since the chi square is a sum of squares of a symmetrical random variable, it is skewed to the right (values with big absolute value, either positive or negative, will represent a big weight for the graph that is not compensated with values near 0). This shows that (a) is true
The more degrees of freedom the chi square has, the less skewed to the right it is, up to the point of being almost symmetrical for high values of k. In fact, the Central Limit Theorem states that a chi sqare with n degrees of freedom, with n big, will have a distribution approximate to a Normal distribution, therefore, it is not very skewed for high values of n. As a conclusion, the shape of the distribution changes when the degrees of freedom increase, because the distribution is more symmetrical the higher the degrees of freedom are. Thus, (b) is true.
Answer:
"0.0125" is the right solution.
Step-by-step explanation:
The given values are:
Random sample,
n = 90
Claims,
p = 20%
or,
= 0.20
By using normal approximation, we get
⇒ 
On substituting the values, we get
⇒ 
⇒ 
Now,
The standard deviation will be:
⇒ 
On putting the above given values, we get
⇒ 
⇒ 
⇒ 
⇒ 
hence,
By using the continuity correction or the z-table, we get
⇒ 
⇒ 
⇒ 
From table,
⇒ 
Answer:
26/52
0.5
50%
(diamond and heart suits)
Step-by-step explanation:
half of the cards in a standard deck are red. So, that'd 52/2 which is 26.
and since its half, you'd end up with .5 and 50%
hope this helps!!