Simply take a value, let's say it's X, you divide by 4/3(remember if you divide by a fraction that you have to multiply the numerator by the reciprocal of that fraction you have in the denominator); therefore, you're going to multiply that X by 3/4, and now we're also going to multiply it by 2/3. Well, 3/4 x 2/3= 2/4, or 1/2. So you're going to be the same as A, multiplying by 1/2