Box A contains 5 dark chocolates and 10 milk chocolates. Box B contains 12
dark chocolates and 12 milk chocolates.
Craig picks a box at random and then
takes out one chocolate at random.
What is the probability that he gets a dark
chocolate?
% (1 d. p.)

5/12

Explanation:
Chances of getting box A or B = 1/2
Chances of getting dark choco in Box A:

P = 5/15 = 1/3

Chances of getting dark choco in Box B:

P = 12/24 = 1/2

The probability of getting a dark choco from a random box is:

P = 1/2(1/3 + 1/2) = 1/2(2/6 + 3/6) = 1/2(5/6) = 5/12

I'm just guessing, but my answer would c. 0 to 300.