# The problem of Hannah’s sweets solved: the GCSE question that stumped Britain’s students

"Hannah's has 6 sweets in her bag prove that n2-n-90=0" #EdexcelMaths pic.twitter.com/nyai7rukFV

— ️♡Gail♡ (@AbigayleWils0n) June 4, 2015

So, what was the answer?

*There are 6 orange sweets and n sweets overall. So, if Hannah takes one, there is 6/n chance of getting an orange sweet. When she takes one,, there is one less orange sweet and one less overall meaning that the probability is now (6-1)/(n-1)=5/n-1.*

*To find the probability of getting the orange sweet both times, multiply the two fractions: 6/n* 5/n-1 =30/n^2-n.*

*It shows the probability of taking two orange sweets (1/3) is: 1/3=30/n^2-n.*

*The denominators then need to be the same, so multiply 1/3 by 30 which would then make 30/90=30/n^2-n.*

*Discounting the 30 on both sides of the equation makes n^2-n=90. By moving 90 onto the other side of the equation, it will equal zero.*

Simple, right?

Read more:http://www.independent.co.uk

**Short URL**: http://www.choicetv.org.uk/?p=4166