Data Sufficiency Question 41

Directions : Each of the following questions consists of a question and two statements I and II given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Read both the statements and.

(BOB Junior Management

Grade/Scale-I Exam. 18.04.2015)

Mark answer (1) if the data either in statement I alone or in statement II alone are sufficient to answer the question.

Mark answer (2) if the data in both the statements I and II together are not sufficient to answer the question.

Mark answer (3) if the data in bith the statements I and II together are neccessary to answer the question.

Mark answer (4) if the data in statement I alone are sufficient to answer the question while the data in statement II alone are not sufficient to answer the question.

Mark answer (5) if the data in statement II alone are sufficient to answer the question while the data in statement I alone are not sufficient to answer the question.

  1. What is definitely the value of ’ $x$ ' I. $\frac{x^{2}}{7}-x+\frac{6}{7}=0$

II. $3^{x-2} \cdot 9^{2 x-3}=9^{5 x-19}$

Show Answer

Correct Answer: 41. (3)

Solution: 41. (3) From statement I,

$ \begin{aligned} & \frac{x^{2}}{7}-x+\frac{6}{7}=0 \\ & \Rightarrow x^{2}-7 x+6=0 \\ & \Rightarrow x^{2}-6 x-x+6=0 \\ & \Rightarrow x(x-6)-1(x-6)=0 \\ & \Rightarrow(x-1)(x-6)=0 \end{aligned} $

$\Rightarrow x=1$ or, 6

From statement II,

$3^{x-2} \times 9^{2 x-3}=9^{5 x-19}$

$\Rightarrow 3^{x-2} \times\left(3^{2}\right)^{2 x-3}=\left(3^{2}\right)^{5 x-19}$

$\Rightarrow 3^{x-2+4 x-6}=3^{10 x-38}$

$\Rightarrow 5 x-8=10 x-38$

$\Rightarrow 10 x-5 x=38-8$

$\Rightarrow 5 x=30$

$\Rightarrow x=6$