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:

The Competition Continues - Game of Timers is a team-based competition based on solving GMAT questions to win epic prizes! Starting July 1st, compete to win prep materials while studying for GMAT! Registration is Open! Ends July 26th

If the product of the integers a, b, c, and d is 1,155 and if a > b >
[#permalink]

Show Tags

07 Apr 2015, 10:00

1

1155 is divisible by 11 from the first glance, which lets us easily split it into 11*105 and then into 11*7*5*3. As it turns out we don't have to think much about possible products of 4 numbers, because we pretty much got 4 numbers for 4 spots and after arranging them in the corresponding order its easy to figure out that the answer is 11 - 3 = 8 which matches answer D

Upon first glance, 1155 and four variables might look really messy. But take the first step – you know it’s divisible b y 11 and that you have to factor it. 1100 is 11*100 and 55 is 11*5, so you have 11*105. And 105 is much easier to divide out since it ends in a 5. That’s 21*5, which is 7*3*5. Once you’ve factored it down, it’s 11*7*5*3, which are all prime, so when 1 has to be less than any of these, that’s exactly a, b, c, and d. You need the biggest minus the smallest, and 11-3 is 8. What may have looked like a big, intimidating number was actually not so bad once you took the first step. It’s always darkest before the light goes on.
_________________

Re: If the product of the integers a, b, c, and d is 1,155 and if a > b >
[#permalink]

Show Tags

05 Mar 2017, 02:06

Hello everybody! I have a confusion, whether this factorization technique is the way to approach such type of question or it's appropriate with the information given in the question. For instance i have a number 910 which is the product of abc where a>b>c and i have to find a-c. If I take factorization technique there are four prime factors of 910, which is 2,5,7,13, so if i take 2,35(5x7),13 then answer is 33. however if i take, 10(2x5),7,13, answer is 6. Because the question ask me that a,b,c,d are integer and integers could b prime and non-prime as well.

Re: If the product of the integers a, b, c, and d is 1,155 and if a > b >
[#permalink]

Show Tags

05 Mar 2017, 02:21

Ahtisham wrote:

Hello everybody! I have a confusion, whether this factorization technique is the way to approach such type of question or it's appropriate with the information given in the question. For instance i have a number 910 which is the product of abc where a>b>c and i have to find a-c. If I take factorization technique there are four prime factors of 910, which is 2,5,7,13, so if i take 2,35(5x7),13 then answer is 33. however if i take, 10(2x5),7,13, answer is 6. Because the question ask me that a,b,c,d are integer and integers could b prime and non-prime as well.

I don't think that questions would be that confusing. Even if there are given just 3 integers (a,b,c) there will be given a>b>c>2.