Aptitude - Numbers - Discussion

What is mean product of even, odd is always even?

@Emi.

It mean that --** 6n (n+1) **--- where 6 is product & n may be even or odd.

That's why if product is even is always give even result whether -- n -- may have even or odd.

Some books write it wrongly 6n2+6n instead of 6n^2 + 6n.

I do not understand this problem. Please explain in detail.

Substitute any number for n.

It will become even number.

The numbers should be 6, 12, 18, 24.

If 46N is divisible by 18 then what is the value of N?

6n^2+6n= 6n(n+1).

Now the number above will always be divisible by 6
And it will be divisible by 12 only when n(n+1) part is even
Eg.6*2=12 ,6*6=36,6*5=30 when we used odd number to multiply with 6 its resultant was not divisible by 12 whereas with even number multiplies by 6 is always divisible by 12.

In case of n*(n+1) always one of the numbers will be odd and another one will be even, Multiplication of odd and even number always results into even number hence it will always be divisible by 12.

@Niranjan.

It would be 8,
because 18x25=450,
And then so, 18x26=468,
So, N would be 8.

If N is even number given expression is divisible by 6 and 12.
But, here N is a natural number.
The given expression is divisible by 6 only.