Question 350 Data Sufficiency 2017 GMAT Official Guide
Question 350 Data Sufficiency 2017 GMAT Official Guide
Video explanation: Is the number of seconds required to travel $d_{1}$ feet at $r_{1}$ feet…
Comments
Mohit Kediasays
The correct answer should be C for question 350 of OG 2017, instead of E. It is possible to answer the question with both the statements combined together.
(d2+30)/(r2+30) > d2/r2 ?
Subtracting 1 from both the sides.
(d2-r2)/r2+30 > (d2-r2)/r2 ?
It is possible to answer the above question.
When we combine statements 1 and 2, our question simplifies to ” Is $\dfrac{d_2 + 30}{r_2+30} \gt \dfrac{d_2}{r_2}$?”, now if we subtract 1 from both sides based on your suggestion, then this inequality simplifies to $\dfrac{d_2 – r_2}{r_2+30} \gt \dfrac{d_2 – r_2}{r_2}$. At this stage, we have to consider two cases, if $d_2 \gt r_2$, then the numerator on both sides is positive and the denominator on the left side is greater than on the right side. In this case we would answer the question as NO. However, if $d_2 \lt r_2$, then the numerators are both negative and the term on the left side becomes greater, and in this case the answer to the question becomes YES. So the statement is indeed insufficient.
Mohit Kedia says
The correct answer should be C for question 350 of OG 2017, instead of E. It is possible to answer the question with both the statements combined together.
(d2+30)/(r2+30) > d2/r2 ?
Subtracting 1 from both the sides.
(d2-r2)/r2+30 > (d2-r2)/r2 ?
It is possible to answer the above question.
GMAT Quantum says
Hi Mohit,
When we combine statements 1 and 2, our question simplifies to ” Is $\dfrac{d_2 + 30}{r_2+30} \gt \dfrac{d_2}{r_2}$?”, now if we subtract 1 from both sides based on your suggestion, then this inequality simplifies to $\dfrac{d_2 – r_2}{r_2+30} \gt \dfrac{d_2 – r_2}{r_2}$. At this stage, we have to consider two cases, if $d_2 \gt r_2$, then the numerator on both sides is positive and the denominator on the left side is greater than on the right side. In this case we would answer the question as NO. However, if $d_2 \lt r_2$, then the numerators are both negative and the term on the left side becomes greater, and in this case the answer to the question becomes YES. So the statement is indeed insufficient.
Dabral