Answer:
The null hypothesis is
, in which x is the proportion tested.
The alternative hypothesis is 
Step-by-step explanation:
A recent article in a university newspaper claimed that the proportion of students who commute more than miles to school is no more than x.
This means that at the null hypothesis, we test if the proportion is of at most x, that is:

Suppose that we suspect otherwise and carry out a hypothesis test.
The opposite of at most x is more than x, so the alternative hypothesis is:

Hello there!
For this you simply need to give both fractions a common denominator!
The easiest way to do this specific problem would be to make the denominator 12. Why 12? Because 4 x 3 = 12.
So:
1/4 --> ?/12 --> 1 (3) / 12 --> 3/12
2/3 --> ?/12 --> 2 (4) / 12 --> 8/12
Total amount of time means the sum (adding them together).
When adding fractions, you MUST have a common denominator! (Which is what we just did).
So 3/12 + 8/12 = (8+3) / 12 = 11/12 hours
Notice how the denominator stayed the same? When adding/subtracting fractions, the denominator stays the same! :)
Hope this helped!
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The answer is x=2 that is the answer
when u have a common a denominator then you just add the numerator that would be 7 and 9. 7 + 9= 16
so ur solution would be 16/22 and then u would simplify by dividing both values by 2.
so the solution is8/11