# Maths help

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#1
These 20 discs are in bag
11, 11, 11, 11
22, 22, 22, 22, 22, 22
33, 33, 33, 33, 33, 33, 33
44, 44, 44
Two of the discs are taken at random from the bag
Work out the probability that the first disc has a smaller number than the second disc
0
1 month ago
#2
what have you thought of so far :/
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#3
(Original post by Qxi.xli)
what have you thought of so far :/
Im so stuck i havent got anything yet
0
1 month ago
#4
(Original post by as551)
Im so stuck i havent got anything yet
I'm not entirely sure either tbh lmao but I think it's solvable once you draw a tree diagram. Maybe try that?
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#5
(Original post by Qxi.xli)
I'm not entirely sure either tbh lmao but I think it's solvable once you draw a tree diagram. Maybe try that?
I tried that but im still really stuck!
0
1 month ago
#6
(Original post by as551)
I tried that but im still really stuck!
Can you post a pic of it?
After you draw one I think it should be fairly easy to solve? You just add the probabilities of when the first disc has a smaller probability than the second I think.
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1 month ago
#7
(Original post by GoodLuckFor2021)
....
you're not allowed to give answers on this forum lol
Last edited by Qxi.xli; 1 month ago
0
1 month ago
#8
(Original post by as551)
These 20 discs are in bag
11, 11, 11, 11
22, 22, 22, 22, 22, 22
33, 33, 33, 33, 33, 33, 33
44, 44, 44
Two of the discs are taken at random from the bag
Work out the probability that the first disc has a smaller number than the second disc
Did you get a answer for this one. I am struggling aswell.
0
1 month ago
#9
I got 239/380 if that helps, idk if it’s right though
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1 month ago
#10
(Original post by Slippysausage123)
I got 239/380 if that helps, idk if it’s right though
Acc I tried it again and got 29/76
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3 weeks ago
#11
(Original post by Slippysausage123)
Acc I tried it again and got 29/76
0
3 weeks ago
#12
i think I have the answer! i believe its
(38.1/4 X 16/19) + (6/20 X 10/19) + (7/20 X 3/19) which gives you 29/76 and 29/76 as a % is 38.1%
Last edited by grace1x; 3 weeks ago
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3 weeks ago
#13
i think you can keep the answer as 29/76 or as % its up to you.
Last edited by grace1x; 3 weeks ago
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