Sample exam question help

[PopcornTime]

Can anyone help out with answering some of the questions from the core data analysis section in the 2017 sample exam?

Q8 Multi choice. Whats the easiest way to do these types of questions without a calc?

Q12 Multi choice. I choice A but the answer is D. Is it because of the phrase "tend to"?

Q16 Multi choice. Why is the answer B and not D? I understand that Jan, Feb, Nov and Dec aren't included in the smoothed plot, but still a little confused.

Q3 short answer b) Where would we know where to put the scatterplot by eye?

Thanks.

[BlinkieBill]

Q8. Without a calculator, the best way is the process of elimination. So firstly, the depedent variable is wrist circumference, so you can eliminate option A and C.
Then, the y-intercept is at around 17.4 so you can elimnate B.
Now it just comes down to the gradient and you'd use the formula m= (y2-y1)/(x2-x1)

Q12. Yes, it is because it says 'tends to' . Option A is a more definite thing that isnt supported by an r-value that is not 1.

Q16. Here you are 'correcting' the sales for seasonality. So you want to change January's value of 1.6 to 1. This is because the value of 1.6 means that it is 60% higher than the average seasonal value. (someone plz correct me if i'm wrong abt this last thing)

Q3 b. You need to graph the line from Q3a. You cannot do this by eye and dont do it by eye because examiners check that you have correctly graphed it. So i'd plot the y-intercept of the equation found in 3a and a couple of other coordinates and then join them.

On a side note: I also just want to make sure that you know, just in case, that these are not from 2017 sample exams. These were the real VCAA exams for 2017.

[VeryJuicyLemon]

Q8. Without a calculator, the best way is the process of elimination. So firstly, the depedent variable is wrist circumference, so you can eliminate option A and C.
Then, the y-intercept is at around 17.4 so you can elimnate B.
Now it just comes down to the gradient and you'd use the formula m= (y2-y1)/(x2-x1)

Q12. Yes, it is because it says 'tends to' . Option A is a more definite thing that isnt supported by an r-value that is not 1.

Q16. Here you are 'correcting' the sales for seasonality. So you want to change January's value of 1.6 to 1. This is because the value of 1.6 means that it is 60% higher than the average seasonal value. (someone plz correct me if i'm wrong abt this last thing)

Q3 b. You need to graph the line from Q3a. You cannot do this by eye and dont do it by eye because examiners check that you have correctly graphed it. So i'd plot the y-intercept of the equation found in 3a and a couple of other coordinates and then join them.

On a side note: I also just want to make sure that you know, just in case, that these are not from 2017 sample exams. These were the real VCAA exams for 2017.

For Q8, the y intercept isn't 17.4

Remember y intercept is when the x is 0 and by judging the values on the x axis, it is no way near 0.

[BlinkieBill]

For Q8, the y intercept isn't 17.4

Remember y intercept is when the x is 0 and by judging the values on the x axis, it is no way near 0.

oops, my bad

[secretweapon]

oops, my bad

The above post is from 3 months ago