Yet another question stumping (UK cricket related metaphor?) me which is rather depressing and a sign of limited progress in being able to think mathematically.
Two consecutive prime numbers have a difference of 6 and a product of 3127 -find the numbers.
Pathetic as it is, all I can seem to do is write ab = 3127 and b-a = 6 and can't seem to get my brain to budge and think laterally, it just seems locked!
Anyone give me a gentle nudge or pointer without revealing too much? Thanks.
Hang on, I think I'm experiencing a 'brain thaw'...... perhaps substitution required???.......so: if a = b-6 then ab = b(b-6) = b^2 -6b = 3127
so b^2 - 6b -3127 = 0 and using the formula one gets b=59 so a - 53.
That helped, working out live on this site - perhaps I should delete it now I've got the answer .....Oh well maybe I'll leave the post as an example of how the brain can suddenly 'unlock'.
