Rachelpaw wrote:

Below one is question.

How many members of Group G are less than 25 years of age?

(1) Exactly 3/5 of the members of group G are 25 years of age or older

(2) The 24 men in group G constitute 30 percent of the group's membership

I can figure out # of group using (2) which is 80 and

# of 25 years of age or older is 48. # of Under 25 years of age is 32.

But how could I know # of less than 25 years of age with 2 statements? I can't figure out # of exact 25 years of age.

So I choose statements (1) and (2) together are not sufficient because I don't know # of 25 years age separately.

but the answer is Both statements together are sufficient, but neither statement alone is sufficient.

Please let me know why.

HI...

you can have two statements of this kind..

1) people LESS than age of 25

2) People GREATER than age of 25..so where do you put EQUAL to 25 in above statements - Either both or noneyou put in both, you are repeating , so it is NONE

also x LESS than 25 means x<25.. so how can you have 25 in it..now statement 1 says -

(1) Exactly 3/5 of the members of group G

are 25 years of age or older

so three categories..

less than, equal to and greater thanhere 3/5 includes equal to and greater than, so left is 2/5 and this tells 2/5 are third category- less than 25

but we do not know how many are total

insuff

(2) it gives you total but not ratio..

insuff

combined

2/5 of 80 = 32

suff

_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372

2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

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