botirvoy wrote:

1. Please, post in relevant folder

2. Dont post the OA with the question.

Now to the question:

x>y>z

0.2x+0.1y+0.1z>0.15(x+y+z)?

Stmt1: x=50; y=20 (implies: z<20 - lets denote it as "LT20")

0.2*50+0.1*20+0.1*LT20>0.15(50+20+LT20)?

10+2+LT2>7.5+3+LT3?

LT14>LT14.5?

Both sides of the inequality are less than 14 and 14.5 by the same amount.

We can answer the question and it is "definately no". Sufficient.

I think you might have invented some new math along with your new notation "LT20"! Let's call that z instead, and rephrase the question, using the equation you set up:

Is 0.2*50+0.1*20+0.1*z > 0.15(50+20+z) ?

Is 10 + 2 + 0.1z > 7.5 + 3 + 0.15z ?

Is 1.5 > 0.05z ?

Is 30 > z ?

That is, the question is just asking whether we can be certain that z is less than 30. Since we know z is less than 20, Statement 1 is sufficient on its own, and the answer is a definite 'yes'.

Alternatively, you could recognize that this is just a weighted average question - the average discount will be weighted by the prices. If the item with the 20% discount costs $50, and the items with the 10% discount cost less than $50, the overall discount must be closer to 20% than to 10%. Statement 1 guarantees that.

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