• 7 CATs FREE!
If you earn 100 Forum Points

Engage in the Beat The GMAT forums to earn
100 points for \$49 worth of Veritas practice GMATs FREE

VERITAS PRACTICE GMAT EXAMS
Earn 10 Points Per Post
Earn 10 Points Per Thanks
Earn 10 Points Per Upvote

## ds question

##### This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 41
Joined: 31 Aug 2008

### ds question

by ket_gmat » Sun Sep 07, 2008 6:52 am
&#9633; 2
+
3 &#8710;
————
&#9689; &#9674;

In the correct addition shown above, all symbols represent different
nonzero digits.
What is th number represented by &#9689; &#9674;?

1. &#9633; = 2*&#8710;
2. 10&#9689; + &#9674; = 95

what is the answer and why?

### GMAT/MBA Expert

GMAT Instructor
Posts: 2574
Joined: 02 Jun 2008
Location: Toronto
Thanked: 1090 times
Followed by:353 members
GMAT Score:780
by Ian Stewart » Sun Sep 07, 2008 8:45 am
If you write a two-digit number x as AB, where A is the tens digit and B is the units digit, that means that x is equal to 10A + B. So 2) above is certainly sufficient; it tells you exactly that the number is equal to 95.

The first statement is insufficient only because there are two possible cases- we could have 22+ 31 = 53, or we could have 62 + 33 = 95. In both cases the sum is a two digit number, and each of the symbols represents a different digit.
If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com

Junior | Next Rank: 30 Posts
Posts: 29
Joined: 20 Jul 2008
Thanked: 1 times
by gurudev » Sun Sep 07, 2008 8:54 am
but how can that satisfy :

&#9633; +3 = &#9633;

is there something wrong in the question....

### GMAT/MBA Expert

GMAT Instructor
Posts: 2574
Joined: 02 Jun 2008
Location: Toronto
Thanked: 1090 times
Followed by:353 members
GMAT Score:780
by Ian Stewart » Sun Sep 07, 2008 9:57 am
gurudev wrote:but how can that satisfy :

&#9633; +3 = &#9633;

is there something wrong in the question....
Perhaps the symbols aren't displaying properly in your browser? There are two different squares here, one white, one black. It' easier to see the problem with letters anyway; it should read:

A2
+ 3B
= CD

where A, B, C and D are distinct nonzero digits. What is CD?

1) A = 2B
2) CD is equal to 10*C + D

• Page 1 of 1