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Plesse could I have help with this question as I really don’t understand it and I have tried but it just doesn’t make sense so please could I have help with the working out shown so I understand for next time please-

There are some people in a cinema
3/5 of the people in the cinemas are children
For the children in the cinema,
Number of girls:number of boys = 2:7
There are 170 girls in the cinema
Work out the number of adults in the cinema
Original post by boobay8
Plesse could I have help with this question as I really don’t understand it and I have tried but it just doesn’t make sense so please could I have help with the working out shown so I understand for next time please-

There are some people in a cinema
3/5 of the people in the cinemas are children
For the children in the cinema,
Number of girls:number of boys = 2:7
There are 170 girls in the cinema
Work out the number of adults in the cinema


Ah yes a classic way of the new specification designing a question that really isn't that hard but is phrased in the most confusing way possible! (I feel your pain with the ratios)

So there's x people in a cinema
We can say 3/5 of x are children so 3/5x = children
If the number of girls to number of boys is 2:7 then 2/9 of the children are girls,
this means that 2/9 of the children (which is 3/5x) are children that are girls

so 2/9 * 3/5x = girls
and we have the amount of girls! so just put that in:
2/9 * 3/5 x = 170

and then rearrange to find x
2/9 x = 170 / (3/5) = 283.333
x = 283.3333 / (2/9) = 1275

so we know there's x people in a cinema (which we now know is 1275), now we use the start of the question again,

I hope I explained it helpfully for you,

feel free to ask for any further queries :smile:
(edited 5 years ago)
Reply 2
Thankyou so much ! That’s very helpful! And ino the new specification says things so difficult this is a higher paper it’s only like my 5th higher paper and it it so difficult this one! Thankyou!
Original post by boobay8
Thankyou so much ! That’s very helpful! And ino the new specification says things so difficult this is a higher paper it’s only like my 5th higher paper and it it so difficult this one! Thankyou!


Yeah I agree the difficulty is quite the challenge in the higher paper, but you're taking the right steps to knowing how to answer the hard questions early.
Reply 4
Thankyou☺️ the paper I am doing is honestly like the end of the higher paper is like throughout it - this question is only number 2 so it’s hard seen as it’s that’s early in the paper.
OMG Q1 on the higher tier is a draggggg!!!!!!! how is it only 2 MARKS!! what a joke LOL
Original post by boobay8
Plesse could I have help with this question as I really don’t understand it and I have tried but it just doesn’t make sense so please could I have help with the working out shown so I understand for next time please-

There are some people in a cinema
3/5 of the people in the cinemas are children
For the children in the cinema,
Number of girls:number of boys = 2:7
There are 170 girls in the cinema
Work out the number of adults in the cinema


OMG I NEED GCSEswagg6 on this lol
Original post by boobay8
Thankyou☺️ the paper I am doing is honestly like the end of the higher paper is like throughout it - this question is only number 2 so it’s hard seen as it’s that’s early in the paper.


TOTES same man, i cant do ratios to sml LOL
Original post by boobay8
Thankyou so much ! That’s very helpful! And ino the new specification says things so difficult this is a higher paper it’s only like my 5th higher paper and it it so difficult this one! Thankyou!


u ******
Original post by LukeT333
Ah yes a classic way of the new specification designing a question that really isn't that hard but is phrased in the most confusing way possible! (I feel your pain with the ratios)

So there's x people in a cinema


Please read the rules about NOT posting full solutions in the forum. It really does not help people.

Please edit your post and just give a hint next time :smile:
Reply 10
I’m confused am I not aloud to ask what I did ? x I didn’t read the rules sorry ☺️
I'm a little surprised this question is in the public domain already.
It's from 4MA1 (Q2, paper 1H) from June 2018.

I would have solved it totally in terms of ratio.

I wonder if the OP had considered / would consider that approach?

If you can find the ratio of

girls : boys : adults

... then the answer / working is very simple.

Question is, can you find the ratio girls : boys : adults ??
It will mean rearranging the fraction 3/5 into the form of a ratio, instead.
In my experience, most students can demonstrate this.

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