If a, b, and c are integers, what is the value of a?
1) (a-7)(b-7)(c-7)=0
2) bc=18
The answer "Both statements together are sufficient"
I just can't understand how it can be sufficient, if we have three unknowns and only two equations.
It seems there is no enough time during real GMAT test to multiply all terms to figure out the answer.
Sorry, if this question has appeared not the first time. I didn't find the answer.
Again GMAT prep problem
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Hi Olika,
That is new for me. Is it from GMAT Prep?
(1) says that a=7 or b=7 or c=7, so INSUFF, as when b=7 'a' can be any other integer.
(2) bc=18, tell us nothing about A so INSUFF
(1+2) if bc=18 then neither 'b' nor 'c' can be 7 (remind that a, b and c must be integers), since 18 is not a multiple of 7. If 'b' and 'c' are not 7 then 'a' must be.
Answer C
That is new for me. Is it from GMAT Prep?
(1) says that a=7 or b=7 or c=7, so INSUFF, as when b=7 'a' can be any other integer.
(2) bc=18, tell us nothing about A so INSUFF
(1+2) if bc=18 then neither 'b' nor 'c' can be 7 (remind that a, b and c must be integers), since 18 is not a multiple of 7. If 'b' and 'c' are not 7 then 'a' must be.
Answer C