Answer:
The appropriate null hypothesis is 
The appropriate alternative hypothesis is 
Step-by-step explanation:
Exactly a year prior to this poll, in June of 2004, it was estimated that roughly 1 out of every 4 U.S. adults believed (at that time) that the war in Iraq was the most important problem facing the country.
At the null hypothesis, we test if the proportion is still the same, that is, of 
. So
We would like to test whether the 2005 poll provides significant evidence that the proportion of U.S. adults who believe that the war in Iraq is the most important problem facing the U.S. has decreased since the prior poll.
Decreased, so at the alternative hypothesis, it is tested if the proportion is less than 0.25, that is:
Answer:
6
Step-by-step explanation:
Cost per item is found by dividing the cost by the number of items. If the woman bought n items for $120, the cost of each item is $120/n. If the woman bought 24 more items, n+24, at the same price, then the cost per item is $120/(n+24). The problem statement tells us this last cost is $16 less than the first cost:
120/(n+24) = (120/n) -16
Multiplying by n(n+24) gives ...
120n = 120(n+24) -16(n)(n+24)
0 = 120·24 -16n^2 -16·24n . . . . . . subtract 120n and collect terms
n^2 +24n -180 = 0 . . . . . . . . . . . . . divide by -16 to make the numbers smaller
(n +30)(n -6) = 0 . . . . . . . . . . . . . . factor the quadratic
The solutions to this are the values of n that make the factors zero: n = -30, n = 6. The negative value of n has no meaning in this context, so n=6 is the solution to the equation.
The woman bought 6 items.
_____
Check
When the woman bought 6 items for $120, she paid $120/6 = $20 for each of them. If she bought 6+24 = 30 items for the same money, she would pay $120/30 = $4 for each item. That amount, $4, is $16 less than the $20 she paid for each item.
Answer:
Step-by-step explanation:
If there are 9 marbles in total and the desired outcome is to pick a green marble then the probability is 
= 
which simplifies down to a third.
Answer:
More males have a job and more females have a job, and the final answer is does.
Step-by-step explanation:
Answer:
Yes
Step-by-step explanation:
There are two cases: Case 1: x is even, so x can be modelled as a generic number 2n, where n is a positive integer. Clearly this product is divisible by two. ... Hence, it is safe to generalise that the term x²-x is divisible by 2 for any positive integer x.
