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Weekly Maths Challenge

Seven Day Maths

Challenge 132: Dice Solutions

I have two fair cubical dice with faces numbered 1 to 6. One is green and one is red. I throw both dice and get a score of p on the green one and q on the red one.

I notice that I can find integer solutions to the quadratic equation x2px + q = 0.

What is the probability that neither p nor q is prime?

What if the two dice used were octahedral, each with their eight faces numbered 1 to 8?


 

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Good luck! 

 


 

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