Go to navigation
It is currently Tue Feb 25, 2020 3:10 am

All times are UTC




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: Bancroft Maths 2017
PostPosted: Sun Sep 22, 2019 3:58 pm 
Offline

Joined: Sat May 30, 2015 10:36 pm
Posts: 39
I need help from Maths experts.

I don't know where to start.


Three boxes (A, B and C) contain red balls or yellow balls or both.
Each box contains the same number of balls.
Box A contains all twelve of the red balls and one-ninth of the yellow balls.

How many yellow balls are there altogether?

How many balls are there in each box?


Top
 Profile  
 
 Post subject: Re: Bancroft Maths 2017
PostPosted: Sun Sep 22, 2019 4:43 pm 
Offline

Joined: Wed Jan 18, 2012 11:41 am
Posts: 9694
Location: Essex
Gee wrote:
I need help from Maths experts.

I don't know where to start.


Three boxes (A, B and C) contain red balls or yellow balls or both.
Each box contains the same number of balls.
Box A contains all twelve of the red balls and one-ninth of the yellow balls.

How many yellow balls are there altogether?

How many balls are there in each box?


Keep upping the number of yellow balls until that number, times 8 - to make the 'added' yellow balls one ninth of the total yellow balls - (or, that number, times 4) gives you the number of balls in total you now have in the first box? Then times the total in the first box by 3?

e.g. 12 red, add 3 yellow, 15 total in that box. 3 x 8, divided by 2, equals 24/2, so 12. Do not that, keep trying...

_________________
Outside of a dog, a book is a man's best friend. Inside of a dog it's too dark to read.Groucho Marx


Top
 Profile  
 
 Post subject: Re: Bancroft Maths 2017
PostPosted: Sun Sep 22, 2019 5:00 pm 
Offline

Joined: Sat May 30, 2015 10:36 pm
Posts: 39
Please correct me if my understanding is wrong.

Do one box have both colours, one box only red and one box only yellow?

If so, box A has both colours?


Top
 Profile  
 
 Post subject: Re: Bancroft Maths 2017
PostPosted: Sun Sep 22, 2019 9:15 pm 
Offline

Joined: Wed Jan 18, 2012 11:41 am
Posts: 9694
Location: Essex
Gee wrote:
Please correct me if my understanding is wrong.

Do one box have both colours, one box only red and one box only yellow?

If so, box A has both colours?


Box A apparently has all the red balls and some yellow balls. So the other two boxes only contain yellow balls.

_________________
Outside of a dog, a book is a man's best friend. Inside of a dog it's too dark to read.Groucho Marx


Top
 Profile  
 
 Post subject: Re: Bancroft Maths 2017
PostPosted: Mon Sep 23, 2019 8:59 am 
Offline

Joined: Fri Mar 10, 2017 4:06 pm
Posts: 643
Box A contains all 12 of the red balls and 1/9 of the yellow balls.

The remaining 8/9 of the yellow balls must therefore be in boxes B and C. 4/9 in box B and 4/9 in box C, as each box has the same number of balls.

Because the number of balls in each box is equal, then if y is the total number of yellow balls we can say:

Number of balls in box A = Number of balls in box B
12 + (1/9)y = (4/9)y
12 = (3/9)y

y = 36


Top
 Profile  
 
 Post subject: Re: Bancroft Maths 2017
PostPosted: Mon Sep 23, 2019 9:15 am 
Offline

Joined: Sat May 30, 2015 10:36 pm
Posts: 39
Thank you so much for all the replies.

Got the answer too once understood correctly.

Find 1/9 of multiples of 9. It has to be more than 18.

So, the next multiple is 27. But the total of the balls won't be equal with 27 balls.

So, the next multiple of 9 is 36.

1/9 of 36 is 4. 12 + 4 = 16 balls.

36 - 4 = 32 balls

32/2 = 16 balls in each boxes.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC


Who is online

Users browsing this forum: MSN [Bot] and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Privacy Policy | Refund Policy | Disclaimer | Copyright © 2004 – 2020