Calculate each probability given that p(a)=0.3 p(b)=0.7 and a and b are independent?

p(a and b)
p(a or b)

1 Answer
May 4, 2017

# P(A nn B) = 0.21 #
# P(A uu B ) = 0.79 #

Explanation:

We have:

# P(A) = 0.3 #
# P(B) = 0.7 #

And also that #A# and #B# are independent, so

# P(A nn B) = P(A)P(B) #
# " " = 0.3 * 0.7 #
# " " = 0.21 #

And:

# P(A uu B ) = P(A) + P(B) - P(A nn B) #
# " " = 0.3 + 0.7 - 0.21 #
# " " = 1 - 0.21 #
# " " = 0.79 #