Part A:
There are 8 possible outcomes.
HHH
TTT
HTH
THT
TTH
HHT
THH
HTT
Part B:
There is 2 outcomes that consist of all head or all tails.
Part C:
You would expect about 6 students to get all head or all tails.
Hope this helps c:
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x + 2x + 9y - 7y
3x + ( 9y - 7y )
3x + 2y
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y = 0x +0
this line is straight up and down so it has a slope of 0 and it never crosses the y axis so it has a y intercept of 0.
Let the speed of the first train be v mph. Then the speed of the second train is:
(v + 50) mph.
Distance traveled by the first train from 3pm to 7pm = 4v miles.
The second train travels 4v miles in 2 hours (from 5pm to 7pm). Therefore the speed of the second train = (4v)/2 = 2v.
However the speed of the second train is also given by (v + 50) mph.
v + 50 = 2v
v = 50.
The speed of the first train is 50 mph and the speed of the second train is 100 mph.
The conclusion that is valid based on the result of the test would be : A. Her students on average, do not take 30 minutes on the quiz, contrary to what the textbook company stated
we can see in the statement that the average student only need about 25 minutes to take the quiz
hope this helps