If b=12a, where a and b are positive integers, then b can be multiple of which if the following integers.

A) 4

B) 6

C) 8

D) 12

E) 24

E) 48

If b=12a, where a and b are positive integers, then b can be multiple of which if the following integers.

A) 4

B) 6

C) 8

D) 12

E) 24

E) 48

\rm{b} = 2^2 \times 3^1 \times \rm{a} \ \text{ where a is from } 1.... +\infty

Now , plug in +ve integer values for a

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Answer are 4,6 and 12.

As per explanation they have taken b=k*x and b=12a (given)

Now they have taken k*x =12a

And then calculate the value for x =12a/k

We need to find x

Case 1: k=a ; x=12

Case 2: k=2a ; x=6

Case 3: k=3a ; x = 4

Case 4: k= 4a ; x=3

Case 5 : k= 6a ; x= 2

Case 6 : k= 12a ; x =1

Thatâ€™s how they have explained this which is beyond my â€śKENâ€ť.

Is this a GregMat question ?

No itâ€™s not. I was doing it from some third party and found this.

Even at first I was not able to digest the explanation. Thatâ€™s why I put it here to check if itâ€™s explained correctly or not.