Bunuel
Given that x/y < 1, and both x and y are positive integers, which one of the following must be greater than 1?
A. x/y^2
B. x^2/y
C. x^2/y^2
D. y/x
E. √(x/y)
\(\frac{x}{y}<1\)
Since x and y are positive integers, we can multiply both sides by y without changing inequality sign.
\(\frac{x}{y}*y<1*y...............x<y\)
Since x and y are positive integers, we can divide both sides by x without changing inequality sign.
\(\frac{x}{x}<\frac{y}{x}\)
\(\frac{y}{x}>1\)
D
Let us check other options
A) \(\frac{x}{y^2}\)
Here we are increasing the denominator of a fraction that is less than 1, so the new fraction will also be <1.
\(\frac{x}{y^2}<\frac{x}{y}<1\)
B) \(\frac{x^2}{y}\)
Whenever x^2<y, the fraction will be less than 1.....x=2 and y=9
\(\frac{x^2}{y}=\frac{4}{9}<1\)
C) \(\frac{x^2}{y^2}\)
Here we are squaring the fraction that is less than 1, so the new fraction will also be <1 as the value between 0 and 1 reduces as we increase the power.
\(\frac{x^2}{y^2}<\frac{x}{y}<1\)
E) The square root will increase the value but will still be less than 1 always.
\(\sqrt{4/9}=\frac{2}{3}<1\)