A very innovative way for solving indeed! Thanks for sharing. Hope solutions like this "Come" to me when I sit to solve.

Specially, even if I plugged in numbers (X=1, Y=6 and Z=1) Both B & C very true. Again I had to Pick (X=2, Y=24 and Z=8) to see that B is the only answer. It took me approximate 3 Mins to do this

We can solve it using units

If x is in m(meters) then y will be m^2 then z will be m^3

A cannot be true as m*m^2/m^3 - m^2/m.. first entity does not have a unit so you cannot subtract it from the second unit which has meter unit

B Can be true as it is meter - meter

C cannot be true : No unit - Meter unit

D cannot be true: √meter unit - no unit

E cannot be true: 1/meter*√meter unit - 1/meter unit

So, answer will be B

Hope it helps!

amidamani13 wrote:

A cube has length x, a surface area y, and a volume z. Which of the following must be true?

A. xy/z - y/x = 0

B. x^2y/z - y/x = 0

C. xz/x^2y - x^2/xy = 0

D. x(√y)/√z - x^2/y = 0

E. (√z)/xy - (√y)/x^2 = 0

Is there a simpler way to solve this rather than taking individual value combinations and checking each option.

Regards,