Help please
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Help please
can someone help me with this question? I can do it with algebra but my son is finding it hard to understand. If you can do this with some other method please help me
In a group of children two thirds said they enjoyed playing football and three quarters said they enjoyed swimming. If 20 of the group said they enjoyed both activities, what was the total number in the group
In a group of children two thirds said they enjoyed playing football and three quarters said they enjoyed swimming. If 20 of the group said they enjoyed both activities, what was the total number in the group
Re: Help please
Draw an overlapping line diagram
Re: Help please
Without further information there isn't a unique answer to this question. At one extreme end of the range you could have the situation where all the children who enjoy football also enjoy swimming (and therefore one quarter like neither). At the other end you could have the situation where all children like one or other sport. Is this the full wording of the question?
Re: Help please
Another great question for bar modelling.
Find the common denominator of quarters and thirds (twelfths).
Draw a long box.
Split it into 12 pieces.
3/4 = 9/12 start at the left of the box and write S in 9 boxes.
2/3 = 8/12 start at the right of the box and write F on 8 boxes.
5 boxes will have F and S. Those are your 20 children. Each box is therefore 4 children.
12 boxes of 4 children each.
48 children.
Find the common denominator of quarters and thirds (twelfths).
Draw a long box.
Split it into 12 pieces.
3/4 = 9/12 start at the left of the box and write S in 9 boxes.
2/3 = 8/12 start at the right of the box and write F on 8 boxes.
5 boxes will have F and S. Those are your 20 children. Each box is therefore 4 children.
12 boxes of 4 children each.
48 children.
Re: Help please
But equally all 2/3 (8/12) children who like football, could also like swimming. in which case 8/12 = 20, so the group is 30 children. You are assuming that all children like one or other, which is not stated.
Re: Help please
The question tells you that 20 like both activities.
The more that you read, the more things you will know.
The more that you learn, the more places you'll go. Dr Seuss
The more that you learn, the more places you'll go. Dr Seuss
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Re: Help please
Yes, ladymuck, it is a full wording question and answer is 48. Thank you moved,that is what I was looking for.
I did put that information into Venn diagram and by considering total number of children x
We get the equation
2x/3- 20+20+3x/4- 20=x
2x/3+3x/4- 20=x
17x/12-x/1=20
5x/12=20
X=48
As you see this is far too complicated
I did put that information into Venn diagram and by considering total number of children x
We get the equation
2x/3- 20+20+3x/4- 20=x
2x/3+3x/4- 20=x
17x/12-x/1=20
5x/12=20
X=48
As you see this is far too complicated
Re: Help please
If that were so, how could you have 3/4 as a whole number?Ladymuck wrote:so the group is 30 children.
More generally, it's unhelpful that the question as posed by the OP does not appear to specify whether or not any of the group likes neither football nor swimming. In the absence of that, is it not correct that an answer of 36 (T) can be proposed viz:
Football (F) 24 (of whom (FS) 20 like swimming)
Swimming (S) 27 (of whom (FS) 20 like football)
Neither football nor swimming (N) 5
and in which case would it not be
FS 20
F not S 4
S not F 7
N 5
T = 36
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Re: Help please
question is not well designed. Class size could even be 60.
Edited
Correct answer is 36 as above
Edited
Correct answer is 36 as above
Last edited by tiffinboys on Sun Jan 04, 2015 11:39 am, edited 1 time in total.
Re: Help please
It can't be 60:
Number only liking football = 25
Number only liking swimming = 20
Number only liking both = 20
Number liking neither = 5
Total = 70
I think 36 is the only other possible.
Number only liking football = 25
Number only liking swimming = 20
Number only liking both = 20
Number liking neither = 5
Total = 70
I think 36 is the only other possible.