there are 11 sweets in a box four are soft centred and seven hard centred sweets two sweets are selected at random a)calculate the probability that both sweets are hard centred, b) one sweet is soft centred and one sweet is hard centred

a) First sweet you pick will be soft centred in 7 out of 11 cases, so the probability is 7/11when you are picking up a second sweet there are only 6 hard centred left and a total of 10, so the probability is 6/10since you want both events to occur you need to multiply the probabilities
b) similar logic here but you need to consider different option of getting 1 each. You could get hard centred first and then soft centred or vice versa. So the probability of the first event is (7/11) * (4/10) since you have 7 options out of 11 and then 4 out of ten. For the 2nd event its (4/11)*(7/10)Then since both events will lead you to desired outcomes you should add the probabilities

Answered by Artem T. Maths tutor

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