Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

I need some help. The first problem I just do not know who to solve. The second question I assumed the answer, but I'd like to understand the reasoning behind it. If I can get some explanations, that will be very helpful. Thanks in advance!

Is the hundredths digit of the decimal d greater than 5?

(1) The tenths digit of 10d is 7.
(2) The thousandths digit of d/10 is 7.

So from 1, we see that the hundredths digit is 7, ie d=0.07 since (1) means that (0.07)10=0.7. So from this, we know that the hundredths digit is greater than 5. sufficient.

From 2, same thing basically. We know that the hundredths digit is 7 because (0.07)/10=0.007 which would make the thousandths digit of d/10 equal to 7.

(1) 7x-2y>0
(2) -y<x>2y, which means x>(2/7)y. So y is not necessarily greater than 0. Take the case of x=5 and y=-1. So (1) is insufficient.

From (2), we see that x+y>0. Again, y is not necessarily greater than 0. Let x=2 and y=-1.

Together, we know that x>(2/7)y and x>-y. Not sufficient. Let x=10 and y=-1. Then the conditions hold. But they also hold for x=10 and y=1. So y could be neg or pos.

Is the hundredths digit of the decimal d greater than 5?

(1) The tenths digit of 10d is 7. (2) The thousandths digit of d/10 is 7.

So from 1, we see that the hundredths digit is 7, ie d=0.07 since (1) means that (0.07)10=0.7. So from this, we know that the hundredths digit is greater than 5. sufficient.

From 2, same thing basically. We know that the hundredths digit is 7 because (0.07)/10=0.007 which would make the thousandths digit of d/10 equal to 7.

So the answer is D. Does this make sense?

I'm having some trouble following this. Isn't it asking for the hundredths and we were able to see the tenths and thousandths? Or are we saying its a repeating decimal?

If I understand correctly, what we need to calculate is for what value of d, when multiplied by 10, do we get a number with a tenth digit of 0.7. Here is the equation:
10d=0.7 --> to find d, simply divide 0.7 by 10 and we get 0.07. Therefore, the hundredths digit is greater than 5.

Statement 2 requires the same process. Does this help?

If I understand correctly, what we need to calculate is for what value of d, when multiplied by 10, do we get a number with a tenth digit of 0.7. Here is the equation: 10d=0.7 --> to find d, simply divide 0.7 by 10 and we get 0.07. Therefore, the hundredths digit is greater than 5.

Statement 2 requires the same process. Does this help?

got it. Thanks for the clarification for the math impaired

Insufficient. x could be 2 and y could be 1 and 7x-2y > 0. It colud also be x = 2, y = -2, then 7x-2y > 0.

St2:
0 < x+y
Since x is positive, this inequality only tells us y is either positive, or a negative that can be cancelled out by a bigger x.
E.g If x = 1000, y = -1, then x+y > 0. If x = 3, y = 3, x+y > 0. Insufficient.