# Probability

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#1
Sheila either walks or cycles to school
The probability that she walks to school is 0.65
If she walks,the probability that she is late is 0.4
If she cycles, the probability that she is late is 0.1
Work out the probability that on any one day sheila will not be late for school
0
3 years ago
#2
(Original post by XxevexX)
Sheila either walks or cycles to school
The probability that she walks to school is 0.65
If she walks,the probability that she is late is 0.4
If she cycles, the probability that she is late is 0.1
Work out the probability that on any one day sheila will not be late for school
Bet Sheila gets a lot of detentions
0
3 years ago
#3
find out all the probabilities of them being late and then add them all together and take away from 1 to find the answer. (Either use a tree diagram or figure it out with just the numbers.)
0
#4
So if she walks the probability that she is late is 0.4/0.65 ??
(Original post by monkeyman0121)
find out all the probabilities of them being late and then add them all together and take away from 1 to find the answer. (Either use a tree diagram or figure it out with just the numbers.)
0
3 years ago
#5
(Original post by XxevexX)
So if she walks the probability that she is late is 0.4/0.65 ??
I don't think you divide them, I think you have to multiply them to get the probability she will be late if she walks. After that do that with the probability she is late whilst cycling, add them together and take from 1.
0
3 years ago
#6
Probability that sheila:
walks=0.65 and is late=0.4;is not late=0.6
cycles=0.35 and is late=0.1;is not late=0.9

so if you need to find the probability of sheila walking and not being late:
0.65*0.6=0.39
AND probability of being not late and cycling:
0.35*0.9=0.315

therefore,the probability of sheila walking or cycling and still not being late:
0.39+0.315=0.705
0
#7
Thank you 😊
(Original post by smiley_21)
Probability that sheila:
walks=0.65 and is late=0.4;is not late=0.6
cycles=0.35 and is late=0.1;is not late=0.9

so if you need to find the probability of sheila walking and not being late:
0.65*0.6=0.39
AND probability of being not late and cycling:
0.35*0.9=0.315

therefore,the probability of sheila walking or cycling and still not being late:
0.39+0.315=0.705
0
3 years ago
#8
(Original post by XxevexX)
Thank you 😊
That's okay😄
0
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