60% have brown eyes....that means 40% do not have brown eyes
40% of 10 = 0.40(10) = 4.....so 4 people do not have brown eyes
probability of first pick not having brown eyes : 4/10 reduces to 2/5
probability of 2nd pick not having brown eyes : 3/9 reduces to 1/3
probability of neither person having brown eyes : 2/5 * 1/3 = 2/15 or 0.13 or 13%