alltimeacheiver wrote:

Material A costs $3 per kilogram, and Material B costs $5 per kilogram. If 10 kilograms of Material K consists of x kilograms of Material A and y kilograms of Material B, is x > y ?

(1) y > 4

(2) The cost of the 10 kilograms of Material K is less than $40.

C trap...

we have two equations... given (2):

From the stem, X+Y=10

From (2) we have 3X+5Y<40

Let’s try a base case where X=Y=5

We would have,

3(5)+5(5)<40.... NO...

Because of that, Y needs to be less than X

——- Y<X

Now, ALWAYS have in mind the question,

Q: X>Y....

You have a DEFINITIVE yes, hence SUFFICIENT.