A box contains only red chips, white chips, and blue chips. If a chip is randomly selected from the box, what is the probability that the chip will be either white or blue?
(1) The probability that the chip will be blue is 1/5.
(2) The probability that the chip will be red is 1/3.
To find : probability of white or blue (which is equivalent to 1-probability of red)
S1 : there is no probability of white -- INSUFF
S2 : red - 1/3
Therefore p(W/B) = 1-1/3 = 2/3
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