What is the value of x?

Question

(1) x(x + 1) = 2450
(2) x is odd

whitehalo · Answer

(1) x(x + 1) = 2450
x^2 + x - 2450 = 0
(x+50)(x-49)=0
x= -50 or x=49
 Insufficient

(2) x is odd
x could be any odd integer with this statement
 Insufficient

Take statements (1) and (2), we find that we can eliminate x= -50
Hence, x= 49

Answer is C

ENGRTOMBA2018 · Answer

x=?

Statement 2 is not sufficient as x=3,5,7,101 ...

Per statement 1:  x^2+x-2450=0

This provides x=-50 or 49

Thus statement 1 is not sufficient.

Combining,

We get x=49 and is thus sufficient. C is the correct answer.

GMATinsight · Answer

Question : x = ?

Statement 1 : x(x + 1) = 2450

We know that 50*50 = 2500
i.e. 49*50 = 2450
but (-50)*(-49) = 2450 as well
So x may be either 49 or -50
 NOT SUFFICIENT

Statement 2 : x is odd 
There are Infinite Odd number and x can be any one of them. So
 NOT SUFFICIENT

Combining the two stateements  
So x may be either 49 or -50 but x is odd
so x can only be 49
 SUFFICIENT

Answer: Option C

vishwaprakash · Answer

Statement 1:
x(x + 1) = 2450

It can be solved to get either X = -50 or X = 49

Hence statement 1 is insufficient

Statement 2 : 
x is odd

there can be countless odd number
Hence statement 2 is insufficient

Combining 1 and 2 we get X = 49

Hence Option C

shohrat6383 · Answer

STATEMENT 1:  2450= 2 * 5^2 * 7^2 =2*25*49=49*50 (prime factorization). However, (-50)*(-49)=2450. So x may be 49 or -50. NOT SUFFICIENT.

STATEMENT 2:  x may be any odd number. NOT SUFFICIENT

STATEMENT 1+2:  STATEMENT 1 tells us that x is 49 or -50. STATEMENT 2 lets us eliminate -50, since it's an even number. We are left with only 49. So x=49. SUFFICIENT.

Correct answer is C.

mbatarget2016 · Answer

1. x(x + 1) = 2450
This quadratic equation gives us two solutions x=-50 or x=49
Hence 1. is Insufficient

(2) x is odd
There are infinite odd numbers
Hence 2. is Insufficient

However when we use statement 2's information in statement 1 we get that the result is x=49
 Hence the answer is C

mvictor · Answer

1. x^2 +x -2450=0
(x-49)(x+50)=0
x=49
x=-50
NS

2. NS

1+2
x=49

bumpbot · Answer

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What is the value of x?

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