WST01/01, (Edexcel) IAL S1 June 2022, Q5, Discrete Random Variables, Expected value, SD

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[imashavithanage]

Your explanation is very clear. Thank you

[sunaynasamreen]

You explain in the best way. Thank you so much!

[sammyboy]

Hi sir, i dont understand why in part e, you did not use addtion but multiplied the probabilities? Im confiused when do you use addition and when to use multiplication in probabilities.

[vinesandeverythingnice]

Sir why did you multiply with 5 in part d why is it 5a+5b=3 but not a+b = 0.6?

[halimabanu]

Why in part b the MS and Sm are not divided by 6?

[HabibaMaarouf-lk]

i don't think 2, 2 could be used in f since the game ends when the spinner lands on 2