I get way to confused with what the question is really asking for in word problems. And the choices are so close to each other , that I often land up chosing the wrong one! Is there a simple way to understand what the question is REALLY asking for ..
A batch of cookies was divided among three tins 2/3 of all the cookies are placed in Either the blue tin or Green tin, and the rest were placed in the red tin. If 1/4 of the cookies were placed in the blue tin , what fraction of the cookies that were placed in other tins were placed in the green tin
(d) 7/ 5
What is this question really asking me to calculate?
If 1/4 of the cookies were placed in the blue tin
, what fraction of the cookies that were placed in other
tins were placed in the green tin
we know that blue tin is given so it is out, now OTHER left, so they are GREEN and RED, so we need to find:
now the only way to solve it easily is picking numbers:
pick multiple of denominator always if it is about ratios.
so 12 will do, which is minimum.
step by step:
A) now we know that 2/3 of 12 cookies are placed in either BLUE or GREEN tins so 8 of cookes are placed in either of them.
B) then the rest 4 are placed in RED tin.
C) then 1/4 of cookes were placed in BLUE tin, so 3 cookies placed in BLUE, and that makes our A clear now we know that A says 8 cookies are in either of BLUE and GREEN, so BLUE has 3 and 5 are in GREEN
D) as we defined above OTHER tins are GREEN and RED right!
RED-4, GREEN-5 ----> gives us 5/9
The answer is C