Question

If x, y, z are positive natural numbers, then which of the following statement is true?
a) The multiplication of x, y, z is odd.
b)The result of the equation (x+y-z) (z-y) is odd and negative if x, y are even and z is odd.
c) The multiplication of x, y, zº is even if only one of these numbers are positive and even.
d)None of these

Answer 1

Answer:

I. If x is divisible by y and y is divisible by z then x must be divisible by z

Let x be 12, y be 4 and z be 2.

So, here we can see that 12 is divisible by 2. Hence true.

II. If x is a factor of y and z then x must be a factor of y + z

Let x be 3, y be 6 and z be 15.

So, here we can see that 21 is divisible by 3. Hence true.

III If x is a factor of y and z then x must be a factor of z/y Let x be 2, y be 4 and z be 6.

So, here we can see that

6/4 is not divisible by 2. Hence untrue.

Therefore, option C is correct.