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Bunuel
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aj13783, the question specifically mentions consecutive integers, therefore ans should be 'D'
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The product of consecutive integers a and b is 156. What is the value of b?

(1) b is prime

(2) b > a


a*b = 156 what is b?
10*11 = 110
11*12 = 132
12*13 = 156

a = 12 or 13, or -12 or -13
b = 12 or 13 or -12 or -13
signs must be the same

1) b = prime, no negative primes; b = 13 (Sufficient)
2) b > a, 13 > 12; b = 13 (Sufficient)

D.
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Hmm second statement got me.

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156 = 2 × 2 × 3 × 13
Consecutive integers so that means 12 × 13.
Is b 12 or 13?

(1) b is prime
b is 13
sufficient

(2) b > a
13 is greater than 12
-12 is greater than -13
insufficient

answer: A
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axb=156
since we have consecutive intengers we can say
b=a+1

therefore ax(a+1)=156

(1) b=a+1
b = prime --> only solutions 13=12+1
sufficent

(2) still only possible solution since we have consecutive intengers 12x13 = 156
sufficent
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Product of consecutive int a and b =156
12x13 = 156
also
-12x-13 = 156

St 1) b is prime number out of 12,13,-12,-13 only prime number is 13. Thus Suff
St 2) b>a 13>12 and -12>-13 so values of b = 13 or -12. Thus NS

Answer A
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The integer 156 can be written as a product of consecutive integers in two ways

156 = 13 x 12
156= -13 x -12

1) b is prime

Prime nos are positive only.

therefore , b=13

Sufficient

2) b>a

b can be = 13 or -12
as 13>12 and -12>-13

Not sufficient

Hence answer should be A
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Bunuel
The product of consecutive integers a and b is 156. What is the value of b?

(1) b is prime

(2) b > a


Kudos for a correct solution.

VERITAS PREP OFFICIAL SOLUTION

You might fall for the trap answer, D. You’ll break down 156 into 13 times 12 (and realize that you can’t break 13 down any further so there’s no other way to recombine the prime factors to find consecutive integers with a prime), and note that b has to be 13 and a has to be 12. So choice A is, indeed, sufficient. And then when you get to statement 2 you’ll think – yeah, freebie. 13 is bigger than 12, so it has to be 13. But wait – why can’t it be -12 while a is -13? You’ve fallen into the trap – you assumed negative! Woe is you…why do you keep falling for these traps?!
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Bunuel
The product of consecutive integers a and b is 156. What is the value of b?

(1) b is prime

(2) b > a


We are given that the product of consecutive integers a and b is 156. If we let a = x and b = x + 1 (or vice versa), we can create the following equation:

x(x + 1) = 156

x^2 + x - 156 = 0

(x + 13)(x - 12) = 0

x = -13 or x = 12

Thus, in no particular order, a and b could be -13 and -12 or 12 and 13. We must determine the value of b.

Statement One Alone:

b is prime.

Since no negative numbers can be prime and 12 is not a prime, the only possible value of b is 13. Statement one alone is sufficient to answer the question.

Statement Two Alone:

b > a

Using the information in statement two, b could be 13 or -12. Statement two is not sufficient to answer the question.

Answer: A
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Bunuel
The product of consecutive integers a and b is 156. What is the value of b?

(1) b is prime

(2) b > a


Kudos for a correct solution.

152 = \(2^2*3*13\) = 12*13 (consecutive integers a*b) or (-12)*(-13)

St I
b is prime
so b has to be 13 and a must be 12 (since prime numbers cant be negative)-----------Sufficient

St II
b>a
If a,b are positive integers then b=13 and a=12
If a,b are negative integers then a=-13 and b=-12 --------------Insufficient

Hence Option A is correct
Hit Kudos if you liked it 8-)
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The product of consecutive integers a and b is 156. What is the value of b?

Stat1: b is prime
b= 13 and a = 12. Sufficient

Stat2: b > a
b= 13 or -12 and a = 12 or, -13. Not Sufficient

So, It is A. :)
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