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    I was revising for my end of year exam which is going to be like the new GCSE, (I am in year 10 BTW and so I am the first to sit the new GCSE.
    Attachment 548461
    Any Ideas on how to solve this..
    Really appreciate it
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    If you let the number of red counters be  n then the number of blue counters will be  4n . Then find the probability of taking a red counter on terms of  n . Then find the probability of taking another red counter.

    Hey, this was a tricky question, but I got it in the end.
    They have seriously made it a little harder lol tbh.

    If you think about it, the ratio for red:blue is 1:4 and therefore in terms of the total, the red counters are 1/5 of the total number of counters and the blue counters are 4/5 of the total counters.

    If you draw a probability tree diagram, you will soon realise that 1/5 and 0/4 won't work and therefore you have to substitute that with an unknown value (x).

    So try to substitute that 1 and 5 with x, so if 1 was x, what would the denominator or (5) be?
    Think about it as a ratio between 1 and 5 (5 = 1 * 5) so in terms of x which is 1, what would 5 be?

    Use this to set up an algebraic fraction that is equal to 6/155.
    If further help is needed, please ask, I know I'm rubbish at explaining but eventually you'll understand.
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