Is the answer E?
Both the statements does not tell us whether c would be even or odd. Even taking them together I do not see a way to determine it.
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Source: Beat The GMAT — Data Sufficiency |
Plug in numbers here.
For statement 1, let's say that c=2 and d=2. These are acceptable numbers, since the make c(d+1)=2(2+1)=6, which is even. And for these numbers, c is even.
But you could also have c=1 and d=1, since 1(1+1)=2, which is even, so those values satisfy the statement. (When you're plugging in on Yes/No data sufficiency, the most important thing is to satisfy the statement.) And here, c is not even, so the statement is insufficient.
Similar deal for statment 2--in fact, you can use the same values. So 2 is insufficient.
And when we look at them together, again, both sets of values work in both statements, so together they're insufficient. So the answer is E.
For statement 1, let's say that c=2 and d=2. These are acceptable numbers, since the make c(d+1)=2(2+1)=6, which is even. And for these numbers, c is even.
But you could also have c=1 and d=1, since 1(1+1)=2, which is even, so those values satisfy the statement. (When you're plugging in on Yes/No data sufficiency, the most important thing is to satisfy the statement.) And here, c is not even, so the statement is insufficient.
Similar deal for statment 2--in fact, you can use the same values. So 2 is insufficient.
And when we look at them together, again, both sets of values work in both statements, so together they're insufficient. So the answer is E.
Matt McIver
Princeton Review Instructor
Princeton Review Instructor
yvonne12, can you post the explanation (if available)? i think the answer is "E" as well.
thanks.
thanks.
Is OA C?? 
to produce odd result, both numbers have to be odd....but from 1) (d+1) and from 2) (d+4), it is impossible to produce odd using the same d...
Can anyone please explain?
to produce odd result, both numbers have to be odd....but from 1) (d+1) and from 2) (d+4), it is impossible to produce odd using the same d...
Can anyone please explain?
