Hiring - A Level Maths students (predicted an A*) or Further Maths students (predicted an A or A* ) to type solutions for worksheets & other resources (also looking for students with very neat handwriting for written past paper model solutions) . Please get in touch via the contact form if interested.
The first box has two red balls. The second box has two blue balls. The third box has a red and a blue ball.
Boxes are labeled but all labels are wrong!
You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball. How many such operations are necessary to correctly label the boxes?
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Maths Revision and Resources For All Maths Courses
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