Question

A jar contains 7 blue cubes, 4 blue spheres, 5 green cubes, and 6 green spheres. If you select an object at random, what is the probability that the object is green or a cube?

Answer 1

Add all the stuff up:
7 + 4 + 5 + 6 = 11 + 11 = 22
probability of a green object or a cube, so add the green objects and the total cubes
11 green objects + 12 cubes. = 23
23 / 22

Answer 2

it is an OR operation.
1) A = event that the object is green
P(A) = (5+6)/(7+4+5+6)
P(A) = 11/22
P(A) = 1/2
2) B = event that the object is a cube
P(B) = (7+5)/(7+4+5+6)
P(B) = 12/22
P(B) = 6/11
3) A or B
P(A U B) = P(A) + P(B) - P(A intersection B)

Answer 3

@callmemaybe16 probability shoul;d never be more than "1"

Answer 4

4) we now need that intersection probability i.e., probability of both happening.
P(A and B) = 5/22
so, going back to (3)
P(A or B) = (23/22) - (5/22) = 18/22