I guess your are selecting them without replacement, if so:
a) P(picking one defective) = 3/12
P(picking a 2nd defective) = 2/11
P(picking a 3rd defective) = 1/10
P(1 and 2 and 3 defective) = 3/12 x 2/11 x 1/10 = 1/220 = 0.0045
b) None defective: P( Non Defective) = 9/12 (follow Same logic):
9/12 x 8/11 x 7/10 = 21/55 = 0.38
Second method using combination:
a) ³C₃ / ¹²C₃ = 1/220 0.0045
B) ⁹C3 / ¹²C³ = 21/55 = 0.38
In this case u can’t use the distributive property. U just multiple whats in the parenthesis (39•5)=195 and that’s ur answer.
Let’s say if the problem said 5(2+1) u can’t use the distributive property bc u have to do what’s in the parentheses first. 5(3)=15
But If u had a problem like 2(4x+6) then u can use the distributive property. This is bc u can’t add 4x+6 bc they aren’t like terms. So u multiple the 2 by 4x which is 8x and the 2 by 6 which is 12 then ur answer would be : 8x+12
A.(x + 1 < -1) ∩ (x + 1 < 1)
(x < -2) ∩ (x < 0) = (x < -2)
b.(x ≤ 0) ∩ (x ≥ 0) = {0}
c.(x < 0) ∩ (x > 0)
= Ф
Option C has no solution.
Answer:
[4.4] I think, but don't take my word for it