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UK Edexcel Maths Exam
mekbots
kieranlaw4
So I as well as thousands of other people in the UK just did the non-calculator maths exam paper, and I was wondering how many of you on here did it too Currently there is a lot of discussion as to how difficult people found the second section and wanted to hear your thoughts about it! Personally I found the paper in general easier than expected but damn the odd question in the second half ;_;
For example what are your thoughts on what was seen as one of the most difficult: "The question told pupils that Hannah had a bag containing a total of n sweets of which 6 were orange. It said the chances of Hannah picking two orange sweets one after the other was one third and then said use that to prove that n²-n-90=0." - http://goo.gl/m5zZnU (The Telegraph).
For example what are your thoughts on what was seen as one of the most difficult: "The question told pupils that Hannah had a bag containing a total of n sweets of which 6 were orange. It said the chances of Hannah picking two orange sweets one after the other was one third and then said use that to prove that n²-n-90=0." - http://goo.gl/m5zZnU (The Telegraph).
Answer
There are six orange sweets and n sweets overall. If she takes one, there is a 6/n chance of getting and orange sweet. When she takes one, there is one less orange sweet and one less sweet overall.
If she took another orange sweet, the probability would be (6-1)/(n-1)=5/n-1. Now, you have to find the probability if she gets two orange sweets so you simply times the two fractions: 6/n * 5/n-1 = 30/n^2-n.
It tells us the probability of two orange sweets is 1/3 which means 1/3=30/n^2-n.
We need to make the denominators the same so simply times 1/3 by 30/30 which would equal 30/90. if 30/90 = 30/n^2-n, then n^2-n=90. if n^2-n=90 then n^2-n-90 will equal zero.
If she took another orange sweet, the probability would be (6-1)/(n-1)=5/n-1. Now, you have to find the probability if she gets two orange sweets so you simply times the two fractions: 6/n * 5/n-1 = 30/n^2-n.
It tells us the probability of two orange sweets is 1/3 which means 1/3=30/n^2-n.
We need to make the denominators the same so simply times 1/3 by 30/30 which would equal 30/90. if 30/90 = 30/n^2-n, then n^2-n=90. if n^2-n=90 then n^2-n-90 will equal zero.
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Thought it was going to be a lot harder, I managed to pull it off but the very last question struck me xD
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My school took the AQA maths exam but the questions on that were just as hard. It is really annoying me that this test is probably going to get the marks lowered for it when the AQA one was just as difficult as it.
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That was a question that looks ominous but as soon as you start is relatively easy.
