In the correctly-worked multiplication problem above, each

Question

Untitled.png In the correctly-worked multiplication problem above, each symbol represents a different nonzero digit. What is the value of ʞ? (1) ʠ is prime (2) ◊ is not prime

Gnpth · Accepted Answer

We can do the prime factorization of 1995.

1995= 5*3*7*19.

Statement-1 :

Since they are only 2 digit numbers.
 
19*7= 133 and since ʠ is prime number -> 7*3=21, are not a possible for ʞʠ .

Also 19*3= 57 and 7*5=35 are not possible as each digit are different.

So only options are

7*3= 21 and 19*5= 95.

Hence the value of ʞ is 9. Sufficient.

Eliminate B, C and E.

Statement-2 :

◊ is not prime. And which is 2 digit number so only value will be 21. As the multiple of other numbers unit digit will be prime and few combination results in repetition of numbers which is not allowed as they are different numbers.

And ʞʠ will be 19*5=95.

The value of ʞ= 9.

So sufficient.

The answer is D.

Bunuel · Answer

Similar questions to practice: PS: ab-cd-aaa-where-ab-and-cd-are-two-digit-numbers-and-aa-136903.html in-the-below-addition-a-b-c-d-e-f-and-g-represent-the-165187.html in-the-correctly-worked-addition-problem-shown-where-the-54154.html in-the-addition-shown-above-a-b-c-and-d-represent-161656.html if-the-symbols-and-each-represent-digits-in-the-followin-175463.html DS: in-the-correctly-worked-addition-problem-above-a-b-c-d-128953.html if-in-the-addition-problem-above-a-b-c-d-e-f-x-y-a-97479.html Hope this helps.

MathRevolution · Answer

Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and equations ensures a solution.

In the correctly-worked multiplication problem above, each symbol represents a different nonzero digit. What is the value of ʞ?

(1) ʠ is prime

(2) ◊ is not prime
 
Transforming the original condition and the question, we have 1995=21*95=95*21. (Since all the digits have different values we can't have 35*57)
There are 4 variables and 1 equation, thus we need 3 more equations to match the number of variables and equations. Since there is 1 each in 1) and 2), E is likely the answer.
Using both 1)& 2) together, both gives us 21*95=1995 thus ʞ=9 and 1)=2). Therefore, D is the answer.

stoned · Answer

I spent a good amount of time on this problem.
But then I realized that GMAT is not the kind of exam where our math skills are tested. It's the reasoning.
So I thought about what could be the 2 line solution and then it struck me that I need to factor 1995.

GMAT is a reasoning test. The sooner we accept this the better the results will be.

rahulbanka · Answer

Prime-factorisation of 1995 = 3 x 5 x 7 x 19

Statement 1
We are given that ʠ is prime
The only two-digit combination of the prime-factorisation that ensures ʠ is prime: €◊ = 21 and ʞʠ = 95. Hence, ʞ = 9, sufficient.

Statement 2
We are given that ◊ is not prime
The only two-digit combination of the prime-factorisation that ensures ◊ is not prime: €◊ = 21 and ʞʠ = 95. Hence, ʞ = 9, sufficient.

Answer is D

KarishmaB · Answer

With alphametics, we first start with the big picture view and figure out what we can.

1995 = 3 * 5 * 7 * 19
We need to split 1995 into 2 factors of 2 digits each. 19 is already a 2 digit factor so to retain 2 digits, we can 
- keep it as it is (but 3*5*7 becomes 3 digit) or 
- we can multiply it by 3 to get 57 which means the other factor will be 5*7 = 35. So the two factors will be 57 and 35 but here they have 5 common digit though we are given that all digits of the two factors are distinct. 
- we can multiply it by 5 to get 95 which means the other factor will be 3*7 = 21 (which is acceptable)

So the two factors are 21 and 95. 
1 is not prime and 5 is. 
Hence each statement alone is sufficient.

Answer (D)

bumpbot · Answer

Automated notice from GMAT Club BumpBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

In the correctly-worked multiplication problem above, each

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Data Sufficiency (DS) Questions

In the correctly-worked multiplication problem above, each

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards