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A bag contains 12 beads 2 of the beads are blue, 1 of the beads are green, 3 of the b

A bag contains 12 beads 2 of the beads are blue, 1 of the beads are green, 3 of the beads are purple the rest are red Julia takes a bead at random what is the probability that this bed is purple or red is 3/4
Original post by Charlotte.g206
A bag contains 12 beads 2 of the beads are blue, 1 of the beads are green, 3 of the beads are purple the rest are red Julia takes a bead at random what is the probability that this bed is purple or red is 3/4

How many are purple do you think?
Original post by Muttley79
How many are purple do you think?

3 off them are purple as it states in the question
Original post by Charlotte.g206
3 off them are purple as it states in the question

And how many red?
Reply 4
Original post by Charlotte.g206
A bag contains 12 beads 2 of the beads are blue, 1 of the beads are green, 3 of the beads are purple the rest are red Julia takes a bead at random what is the probability that this bed is purple or red is 3/4

Let's seperate the beads into their colours:
2 blue 1 green 3 purple
There are 12 beads in total so you can figure out the number of red beads.


P.s.
P(A or B) = P(A)+P(B) - this is the 'rule' you need to answer this q.
(edited 3 years ago)
Original post by Da14a
Let's seperate the beads into their colours:
2 blue 1 green 3 purple
There are 12 beads in total so

It's against the rules to post a solution - please edit your post :smile:
Reply 6
Original post by Muttley79
It's against the rules to post a solution - please edit your post :smile:

Wow, I had no idea - I thought your posts were just unhelpful. Looks like I was the fool all along :hahaha:
Original post by Da14a
Wow, I had no idea - I thought your posts were just unhelpful. Looks like I was the fool all along :hahaha:

I was trying to get the OP to get the answer with a hint.

It's good to have people helping - just give a hint - the rules are in a sticky in the Maths forum :smile:
5/6?
Reply 9
Original post by tinygirl96
5/6?

Are you claiming this is the answer to the original question?

How did you arrive at that result?
I can work out the answer but am confused by the very last part of the question. Is that 3/4 supposed to be in the question?
Reply 11
Original post by Catherine1973
I can work out the answer but am confused by the very last part of the question. Is that 3/4 supposed to be in the question?

I wasn't sure whether the OP was quoting the answer and wanted to know how to work it out, or was suggesting it as their answer :smile:
Yes that makes sense.
A tree diagram would help.
Original post by Da14a
Let's seperate the beads into their colours:
2 blue 1 green 3 purple
There are 12 beads in total so you can figure out the number of red beads.


P.s.
P(A or B) = P(A)+P(B) - this is the 'rule' you need to answer this q.


whats the answer to this question
Reply 15
Original post by YerMaLad
whats the answer to this question

So we know that there is 6 coloured beads other than the red beads.
We know that there is 12 beads in total.
therefore: 12 - 6 = 6 red beads
we also know there are 3 purple beads
so probability of picking a red bead only: 6/12
probability of picking a purple bead only: 3/12

Now the question says: 'what is the probability that this bead is purple or red?'
This means we must use the AND rule:
P(A or B) = P(A)+P(B)
what this means is that we just add the probabilities of one of the two events occurring
Reply 16
Yes that it the question
Whats the answer

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