What is the ratio of x to y? (1) 0.8x + 0.5y = 40 (2) 0.625y = 50 – x

we need x/y = ?

(1) 0.8x + 0.5y = 40

8x+5y = 400 = > x =\(\frac{400-5y}{8}\)
ratio \frac{x}{y}\(\)= \(\frac{400-5y}{8 * y}\)
This will have different values depending on valve of Y .

So clearly NOT Sufficient .

(2) 0.625y = 50 – x
same as above equation , Not Sufficient

So answer D .

Here the thing is, if the equation is ax+by = C form , we cannot simply express X only in terms of Y to get a ratio ,
there is always a C involved which we cannot express as x or y .

Kudos , if my point is clear to you

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