There are two boxes of markers.The first box has only red

Question

There are two boxes of markers.The first box has only red, orange and yellow markers. The second box only has yellow, green and blue markers. If a marker is chosen at random from each of the boxes , is the probability that both markers will be yellow less than 30% ?

(1) Four out of 12 markers are yellow
(2) The probability of selecting a red or orange marker is 3/5 and The probability of selecting a green or blue marker is 2/7.

Doubt- will there be any case in which the probability as per statement (a) exceed 30 % to get answer Yes as well as NO

ankushbassi · Answer

Manik,
Stmt 1 does not give us the total number of yellow markers in each of the boxes,thus does not help anyway in getting the probability.

Manik12345 · Answer

But it does gives total markers=12 and yellow markers =4.. SO if we assume any combination like let it be 3 out of 9 and 1 out of 3

then prob will be 3/9 * 1/3 =.108 =10.8% WHICH IS LESS THAN 30%.

Similarly we can assume any combination like 2/6 and 2/6 etc. all are giving less than 30 only

manpreetsingh86 · Answer

well i don't think probability greater than or equal to 30% is possible. the maximum that we can get is 27.2% . This case is possible if we assume that one of the box contains only 1 marker which is yellow and the other box contains 11 marker out of which 3 are yellow. then the required probability will be (1).(3/11)=27.2%

Manik12345 · Answer

Actually it is in the question that Ist box has 3 types of markers. So atleast 3 are going to be there. But anywayz the probability is not exceeding 30% for those cases

pretzel · Answer

How do we actually solve this question with statement 2? LCM 35?

KarishmaB · Answer

I don't know which source you are using but the questions are very low quality. 
For example, statement 1 does not clarify whether we are talking about box 1, box 2 or combined. 
Statement 2 does not clarify that the probability of selecting 1 red or orange marker from box 1 is 3/5 or the probability of selecting 1 red or orange marker from both boxes combined is 3/5 Same for green/blue marker. 
Also, I think data in the two statements contradicts. Say stmnt 2 has given combined boxes probability. Say there are 35 total markers. 
P(Red/ORange) = 3/5 = 21/35
P(Green or Blue) = 2/7 = 10/35
So you have 4 yellow markers out of total 35 markers! I don't know how they get 4 out of 12 in stmnt 1. 
If you look at them separately, again there is a problem
P(Red/Orange) = 3/5 so out of 5 total markers in box 1, 2 are yellow
P(Green/Blue) = 2/7 so out of 7 total markers in box 2, 5 are yellow
So 7 total yellow markers out of 12 total markers in both boxes combined!

My suggestion will be to use a quality GMAT question source.

Manik12345 · Answer

Hi Karishma,

For statement 2- it is that probability of getting red or orange from box 1 and green or blue from box 2.
Hence it will provide us the info for selecting yellow from both boxes.

But for statement 1- we will get probability to select 4 out of 12 total markers less than 30% r8 for any combination ?

There are two boxes of markers.The first box has only red

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There are two boxes of markers.The first box has only red

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