Hard tree diagram word problem help

Watch this thread
shainaaa14
Badges: 11
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 2 years ago
#1
Some of the children at the school arrive by car.
- 60% of the children at school are boys
- 20% of the boys arrive at school by car
- 60% of the girls at school arrive by car
What is the probability a child chosen at random at school arrives by car?

Please help!!!
0
reply
nzy
Badges: 17
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 2 years ago
#2
Have you drawn the tree diagram?
0
reply
shainaaa14
Badges: 11
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report Thread starter 2 years ago
#3
(Original post by nzy)
Have you drawn the tree diagram?
Yes but can you please tell me the workout as I am confused.
0
reply
nzy
Badges: 17
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#4
Report 2 years ago
#4
If you've filled in the probabilities for each branch of the diagram, do you know how to calculate the probability that a chosen student is a boy who travels to school by car, for example?
0
reply
shainaaa14
Badges: 11
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#5
Report Thread starter 2 years ago
#5
(Original post by nzy)
If you've filled in the probabilities for each branch of the diagram, do you know how to calculate the probability that a chosen student is a boy who travels to school by car, for example?
no
0
reply
nzy
Badges: 17
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#6
Report 2 years ago
#6
Multiplying the probability along each branch of the diagram will give you the overall probability of that 'path'.
So, for a the student to be a boy who arrives at school by car, you'd need to multiply the probability that the student is a boy with the probability that a boy arrives by car.
1
reply
the bear
Badges: 20
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#7
Report 2 years ago
#7
so you do not actually need to use a tree ? a 2 way table might be easier.

also you can choose a number for the total pupils....1000 is probably convenient ( it does not matter if it does not seem like a real world amount of pupils etc )
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest

Does school Maths prepare people well enough for the future?

Yes, it gives everyone a good foundation for any future path (49)
29.88%
Somewhat, if your future involves maths/STEM (72)
43.9%
No, it doesn't teach enough practical life skills (41)
25%
Something else (tell us in the thread) (2)
1.22%

Watched Threads

View All