marbels

[DavoodBeater]

Bag A contains red, white and blue marbles such that the red to white marble ratio is 1:3 and the white to blue marble ratio is 2:3. Bag B contains red and white marbles in the ratio of 1:4. Together, the two bags contain 30 white marbles. How many red marbles could be in bag A?

1
3
4
6
8

OA: [spoiler]6

the number of white marbles in bag B must be multiple of 4 and 30-(white marbles in bag B) must be multiple of 3.[/spoiler]

[logitech]

First of all, you should not copy paste the explanation but thanks for the OA.

A

R/W =2/6
W/B = 6/9

B

R/W=1/4

6x+4y=30

6 + 24 and 18 + 12 are the only two options

Since the R/W is 1/3 in A

6/3 = 2 or 18/3=6 are the options

[cramya]

Thanks for the nice problem Davood!

Personaly I dont see why we cant post an explanation. It only adds more value to the post. Its another solution or an approach from may be a different perspective.

M all in for the explanations!!!!

Regards,
Cramya

[logitech]

Thanks for the nice problem Davood!

Personaly I dont see why we cant post an explanation. It only adds more value to the post. Its another solution or an approach from may be a different perspective.

M all in for the explanations!!!!

Regards,
Cramya

Cramya is in the Land of Wonders once again...

[cramya]

Cramya is in the Land of Wonders once again

Whatever that means, hv no clue. Anyways...

Regards,
CR

[logitech]

Cramya is in the Land of Wonders once again

Whatever that means, hv no clue. Anyways...

Regards,
CR

Oh you know..Dont play dumb with me!

[cramya]

Oh you know..Dont play dumb with me!

U can say it all year long but trust me on this ;I aint got a clue what u have said above, I could seriously care less...

[DavoodBeater]

thanks fiends for your discussions
but i believe that the solution is not needless.
since it gives us one way and i am seeking for other ways, maybe the easier and faster one.
and it 's in spoiler form, so you can skip it easily and post your solutions.
and last, it was not copy paste from the solution logitech

[KICKGMATASS123]

guys i understand what is done here..


but it just feels like a leap to the last step..

I find it overwhelming trying to do it in under 2 mins.. Can someone help?

[Vemuri]

guys i understand what is done here..


but it just feels like a leap to the last step..

I find it overwhelming trying to do it in under 2 mins.. Can someone help?

In Bag A: The ratios are given as:

R W B
1 : 3
--- 2 : 3

So, the ratio can otherwise be written as 2:6:9 (Red : White : Blue)

In Bag B: The ratios are given as:

R W
1 : 4

The information provided to us is that together the 2 bags have 30 white balls. To get 30 white balls (based on the ratio), there should be 18 white balls in bag A & 12 white balls in bag B. If 18 (6*3) white balls are in bag A, then there should be 2*3=6 red balls in bag A.

Hope this helps.