This one is straight E, we know nothing about the ratio of # of boys to the # of girls in the group.

Question: is (# of children with brown hair in the group)/(total # of children in the group)>0.5?

Consider total # of children in the group to be 100. Now, even when we combine two statements we would have the following: 30 children are girls with brown hair and 70% of the boys have brown hair. If # of boys is 10 then 7 boys would have brown hair and total # of children with brown hair would be 30+7=37<50. But if # of boys is 70 (in this case there would be only 30 girls in the group and all girls in the group would have brown hairs) then 49 boys would have brown hair and total # of children with brown hair would be 30+49=77>50.

Answer: E.
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heres how i thought about it:

even if you know the percentages, you still dont know the # of boys and girls in the group.

that makes it impossible to solve this hence E. (70% of Boys , 30% of girls but total # will make the final determination).

Venn diagrams could be used if there was more info....

IMO: E

1) Not sufficient as we don't know the number of boys and girls
2) Not sufficient as brown haired people can be more than 50 or less than 50 depending on the number of boys.

Yes this was simple E.Data is not enough to find a value for each sentence.

If sentence 2 was - 30% of children are girls 'and' all of them have brown hair; answer would be different

Your replies saying 'u need to know the numbers" are strange.
The question asks you about PERCENTAGE of children not number. So what on earth do we need the numbers for?
if there are 100boys then 70 are brown heads.
if statement 2 had said "30% of girls are brown heads" , both cud av bn sufficient and we pick C.
But it said "Brown hair girls are 30% of the group" instead of 30% of girls.
So it's E.
Better explanation

we still need to count
suppose there are 100 children. number of boy is x, number of girl is 100-x
0.7x is boy is brown hair, not sufficient
30 is girl is brown hair, but boy with brown hair can be 1 or 70, not sufficient

both condition
0.7x+30>50 is this true
x>20/0.7, we do not have this. so we can not know for sure. answer E.

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