aman88 wrote:At the Butterfly Scout Cookie Chow Down, each girl was given equal time to decorate as many cookies as possible. If the winner took an average of 20 seconds to decorate each cookie, how many cookies did the second-place finisher decorate?

(1) The second-place finisher was only able to decorate at half the rate of the winner.

(2) The winner decorated 15 more cookies than the second-place finisher.

OA C

Help me solve this problem.

Thanks.

Let's understand what the objective is:
We need to determine if the given information is sufficient to determine the number of cookies decorated by the girl who finished second.

Let's look at Statement 1:
The second-place finisher was only able to decorate at half the rate of the winner.

This clearly does not give us any "numbers" to help us determine the number of cookies decorated by the girl who finished second.
NOT SUFFICIENT

(However, it does give us a relationship between this girl and the winner.
i.e. let's assume that the winner decorated "x" cookies.
Since, the girl in second place decorated at half the rate of the winner, she decorated "x/2" cookies.
Let's see if this is of any help later)

Statement 2
The winner decorated 15 more cookies than the second-place finisher.

Okay, so we have some numbers here.
Let's assume that the winner decorated"x" cookies.
Then, using statement 2 we get that the girl in second-place decorated "x-15" cookies.
But we still don't have the value of "x"

Now, lets combine 1 & 2.
x-15=x/2
i.e x=30
Thus, the girl in second place made x-15=30-15=15 cookies

Answer: [spoiler](C)[/spoiler]

Hope this helps

Cheers,
Taz

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