From question stem:
a = 12 * k1 = 2^2 * 3 * k1
b = 2 * 7 * k2
So we have: a^2 * b = 2^5 * 3^2 * 7 * k1^2 * k2
Also 216 = 2^3 * 3^3
If a^2 * b is multiple of 216 then we will need one more 3 from either k1 or k2, i.e. from either a or b.
(1)From st.1 we get a = 2^4 * some integer. But we are not sure whether we get an extra 3 or not. So it’s not sufficient.
(2)From st. 2 we have b = 2^2 * 3. So we get an extra 3 that we required. So it’s sufficient.
Thus answer choice B
a = 12 * k1 = 2^2 * 3 * k1
b = 2 * 7 * k2
So we have: a^2 * b = 2^5 * 3^2 * 7 * k1^2 * k2
Also 216 = 2^3 * 3^3
If a^2 * b is multiple of 216 then we will need one more 3 from either k1 or k2, i.e. from either a or b.
(1)From st.1 we get a = 2^4 * some integer. But we are not sure whether we get an extra 3 or not. So it’s not sufficient.
(2)From st. 2 we have b = 2^2 * 3. So we get an extra 3 that we required. So it’s sufficient.
Thus answer choice B
