Subject: General Aptitude · Chapter: Ratio and Proportion · Exam: · Marks: · Difficulty:
Is x2 : y2 < 1? (M.A.T., 2006) I. (y – x) (x + y) = 40% of 60 – 120% of 20 II. x < y
Answer
SELF-PRACTICE — the source book printed no answer.
Nothing is invented here, so this question has no answer on record.
Explanation
I. $(y-x)(y+x) = \left(\frac{40}{100}\times60\right) - \left(\frac{120}{100}\times20\right) = 24-24=0 \Rightarrow y^{2}-x^{2}=0 \Rightarrow x^{2}=y^{2} \Rightarrow \frac{x^{2}}{y^{2}}=1$. So, $x^{2}:y^{2} \nless 1$. II. $x<y \Rightarrow x^{2}<y^{2} \Rightarrow \frac{x^{2}}{y^{2}}<1 \Rightarrow x^{2}:y^{2}<1$. Thus, either I alone or II alone gives the answer. $\therefore$ Correct answer is (c).
Explanation as extracted from the printed page; notation may be imperfect.