# Probability

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Thread starter 2 years ago
#1
A Bag contains n counters.
One counter is blue and the rest are red. Two counters ae taken at random from the bag.

A)Express, in terms of n, the probability that a counter of each colour is taken. Give your answer as a fraction in it's simplest form

B)The probability that a counter of each colour is taken is 0.125, How many red counters are in the bag?
4
2 years ago
#2
1
2 years ago
#3
I came in to rowlock OP for not knowing how to do the volume of a sphere TBH.

Now I'm going to rowlock them for misleading thread titles and for not knowing how to do probabilities.
3
2 years ago
#4
I also am stuck on this question and was stuck on it. Generally, probability as a whole is not that challenging but this is very confusing as it requires us to express it in terms of n and we dont really have any numerical values so i mean im really stuck on it so if you can help, even a little, it will be greatly appreciated. Thanks.
1
1 year ago
#5
You didn’t answer part B which is where I’m stuck on the same question. Can someone help with this please?
0
1 year ago
#6
TSR is a place to answer or to get help from perplexing question, even if that is homework. I don't see a problem with getting help or an explanation on how to answer the question.
0
1 year ago
#7
(Original post by drangonfruit)
A Bag contains n counters.
One counter is blue and the rest are red. Two counters ae taken at random from the bag.

A)Express, in terms of n, the probability that a counter of each colour is taken. Give your answer as a fraction in it's simplest form

B)The probability that a counter of each colour is taken is 0.125, How many red counters are in the bag?
i know i'm a year late but:
a)2/n
b)15
2/n=1/8(0.125)
x by 2
2/n=2/16
so 16-1=15 (cus only 1 blue counter).
1
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