Question

Gwen has recently purchased a cottage. She has arranged

to have well dug on the property. One in five wells that
were dug recently in the vicinity were dry, and 30% of the
others were contaminated. Find the probability of each of
the following:
a) Gwen's well will not be dry
b) Gwen's well will be uncontaminated, given that it is not dry.
c) Gwen will have safe‐drinking water from her well.
d) Gwen will not have safe‐drinking water from her well.

Answer 1

A. i think would be the correct answer

Answer 2

a) 1 - (1/5) = 0.8.
b) 0.7.
c)
`0.8*0.7=0.56`
d) 1 - 0.56 = 0.44.