Two ways to solve
Method 01: Cross multiplicationWe need -
\(\frac{x+w}{y+w}\) > \(\frac{x}{y}\)
As all the numbers are positive we can cross multiply
\(y(x+w) > x(y+w)\)
\(yx+yw > xy+wx\)
We can subtract yx on both sides of the equation and divide by w
\(y > x\)
So basically we need to find if \(y > x\)
Statement 1 - Gives us what we need, hence sufficient.
Statement 2 - Doesn't provide the required information. Hence not sufficient.
Hence A is sufficient.
Method 02: Properties of Ratios & FractionsThe little algebra of method 1 can be avoided if we use the properties of ratios -
When x, y and w are positive -
\(\frac{x+w }{ y + w}\) > \(\frac{x}{y}\); when \(\frac{x}{y}\) is a proper fraction, i.e. x < y
\(\frac{x+w }{ y + w}\) < \(\frac{x}{y}\); when \(\frac{x}{y}\) is improper fraction, i.e. x > y
Hence to answer "
Is \(\frac{x+w }{ y+w}\) > \(\frac{x}{y}\)", we need the information if \(\frac{x}{y}\) is proper fraction or is it improper fraction.
Statement 1 gives that information.
IMO A
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