Edexcel s1 June 2016 unofficial mark scheme

I reckon 55 for an A

But the new value was exactly the same as the mean, so the SD (average distance from mean) can't increase. Others said it stayed the same, but I wrote that it decreases, because now the average distance from the mean is slightly less (as n has increased by 1 but deviance hasn't changed).

I said mean stays the same and then gave an explanation that this was because the new value was equal to the mean.

I said that s.d would stay the same as it is 0 deviations above the mean (I know this part is wrong)

How many marks would I get it? The question was out of 3

Crap was the question for the one below the histogram (w>3) or (w<3) cos I got 0.7.... ??

The standard deviation tells you on average how far the values are away from the mean so since the new value was zero away from the mean the average spread would decrease you probs got one mark for the mean part

Was it out of 3 marks?

I thought it was 2? 1 mark for each. I hope it isn't 3

If it was 2 marks that would be brilliant. Can anyone confirm how many marks was it out of?

1 mark for mean and 2 for SD

Ok, I managed to get all my answers stored in my calculator at the end, this is what I got. Not 100% sure on all of them, but we can compare.

Question 1Question 2Question 3Question 4Question 5Question 6

1 mark for mean and 2 for SD